RT 178 Side by Side seating Install and Measurements

[fcscott]

LONG READ - I looked long and hard for measurements to add side by side seating to the front deck of My RT178 non-crappie version but never found anything written anywhere so I had to do it the hard way. For prosperity and to help others wanting to do this to their boat, here is a synopsis of the job along with measurements if your so incline to do the job yourself. Be forewarned, this is about a six-hour job if you go to the extent i did to make it look factory. So, I removed the trolling motor pedal tray to access under the deck. I found that the pedestal base plate was attached to the deck with stainless 1/4x20 tapered head machine bolts which passed through both the deck and square tubing bracing under the deck which measures 1 1/2" inches thick by 2 1/2" wide. I used bolts that were 2 1/2" long to attach the new base plates which worked fine. I also found that there is existing sub structure / bracing under the deck area (see pictures) which i assume is for additional buddy seating like is offered in the crappie version boat. This additional sub-structure measured the same as the center sub-structure for the center baseplate simplifying matters and provides a sound bracing for adding additional base plates in the same plane as the single center plate. I wanted to make this look like a factory installation which meant that the carpet would need to come up to hide the baseplates. That meant that either i would have to replace the carpet or gently pull the carpet back. I chose to re-use the old carpet because I did not want to replace all the carpet in the boat and new carpet would not match due to fading. So to start, after all the measuring with my head stuck in a hole, I marked the carpet with a sharpie where i wanted the center of my new base plates to be and where they would intersect the sub-structure for a solid foundation. With the attached measurements you should be able to skip this part of the process,, your welcome. Once Marked, I drilled an 1/4"hole through the deck and this was my starting point, just a single hole in the carpet at this point. Next, I drilled out the rivets which attach the large storage lid piano hinge with a 3/16" drill bit and removed the lid so i could access the carpet that is pinched by the hinge. Once that was out of the way and with the rod locker and compartment in front of the console lids open, the full length of the rolled edge tucked carpet was accessible, almost. From this hinge point "seam" to the bow of the boat it is one piece of carpet. The two corners of the carpet at the left and right gunnels are tucked into a very thin crack and it takes some effort to remove the tucked end from the crack. I did this with a small hook. Once the corners were liberated, i began using the hook to lift the carpet away from the rolled lip until it was lifted all the way from left to right. The edges of the carpet are just kind of tucked up under the gunnels with some sporadic glue here and there and was not difficult to pull loose. I then began to work the carpet free from the deck working towards the bow and only as far forward as was needed to mark and drill the rest of the holes for the new base plates. I'll note there that the carpet is "pinched" between the baseplate bushing and the plate itself which prevents the carpet from coming loose when walked upon, more on that later. To do as little damage as possible to the carpet while peeling it back, I used an oscillating tool with a flat scraper attachment between the carpet and deck. This worked pretty good and also used it to remove most of the heavier glue that was left on the deck sheeting. Once the carpet was laid back enough on both sides (up to the center baseplate bushing), It was time to remove the old glue from the deck with goo gone or similar product. I then marked hole locations on the deck sheeting for attaching the new baseplates with a template that I had made from card stock, all based on the previously drilled center hole. (again, refer to the attached “Simplified Drawing” to save some time). I used a straight edge to align the attachment holes in the new baseplate to the holes in the pre-existing center baseplate. Alas, the holes did indeed pass through both the deck and substructure beneath, as was hoped for! Once the six bolt holes were drilled, I then used a 3" hole saw to drill the hole for the pedestal socket (using the same pilot hole that was drilled at the beginning) which was larger than what i actually needed but gave me a little fudge factor. (I used the Attwood SP-67739-T Lock’N-Pin ¾-Inch Pin Base , 7x7-Inch Base, Threaded, Acetal Bushing, Pre-Drilled for Mounting) but did cut the locking nut off the bottom because I did not want it and it wasn’t lined up properly anyways to accept the pedestal pole. Be sure to measure the bottom of the plate you're using to make sure it will be big enough to accommodate the bell on the bottom of the plate. Once all drilled, repeat for the other base. Before you mount the plates, the bushings need to be removed so that you can “trap” the carpet between the bushing and plate, as mentioned earlier. They are in there tight! For this step, I rigged a puller (see pic) using all thread and some washers, two of which I ground down to be a perfect fit inside the tube that holds the bushing. By doing so, you prevent any damage to the bushing and post fit. I used a large socket for the top side of the bushing and using the tool, pulled the bushing up and out. I use the same tool to pull the bushing back into the tube after the carpet was glued back down. Okay, once the bases are mounted down using the tapered head ¼ X 2 ½ inch stainless bolts and nylocks, time to clean up and glue the carpet back down, self-explanatory here. Once carpet is glued back down (I used DAP Weldwood “original” contact cement) and tucked in, trim the center holes in the baseplates with a fine point SHARP exacto blade to get a good clean cut that is no larger than the ID of the tube without bushing in place. THEN use the tool again to pull the bushing back into their tubes (lubricate with silicone) and pinch the carpet between the bushings and plates. Reattach the large deck lid piano hinge using 3/16 aluminum rivets being sure the holes are drilled deep enough to accept the length of the rivet. Reinstall the TM pedal tray and hopefully you’re done. If you are using my simplified drawing to layout your measurements, I used two carpenter's squares pushed into the gaps between the rod locker and compartment in front of the console along with a straight edge to measure off of, see pic. LOL Disclaimer, this post is assuming that your boat measurements are the same as what i found but of course, you should confirm that it will work for your RT178. Good luck and I hope this helps.