Got a Marcum Shuttle Kit. Going to adapt my Helix 7 G2 Humminbird to it. Biggest thing is to replace Marcum cord with the Humminbird one. Only obstacle is the 5782 phillips head screws holding the bottom on. Exaggeration of course but not too far off.
Only other problem is bolt pattern for the Helix will not match up. Will probably drill the Helix gimbal to match the Marcum pattern.
The good news is my local lakes finally have a coating of ice on them. Not thick enough for walking on yet. But weather outlook next few days look favorable.