Got home after work and started in on it.....had to mount it on top edge beside me on driver side. Was really apprehensive about drilling...put tape down and the holes were drilled perfectly. Went to start screw just to see if it would be a smooth in and after 2 two turns, Crack, gel coat cracked! Just a little around the hole opening, but still yet. Evidently the 1/8 hole suggested by garmin for their screws was a bit small....so I found a little bigger bit and went through again....all went well after that, but I decided to leave a little piece of tape over the cracked gel coat on the one hole....man it left a lump in my throat but chit happens  so now it's on to the transom and also running the transducer cord....eh that part doesn't sound like to much fun. Gonna take the power cords from both the DV ando sv and solder the communication wires tomorrow and prep the power cord. I did notice that the sv head unit has a screw and crimp on the backside and a diagram grounding to the battery. My DV didn't have this but does have 4 threaded holes behind the head unit