i have a gd 35sd tall transom model w/three blade prop on an 1860 lowe all weld 3 degree vhull.(i know this isnt the ideal boat but its what ive got and it works for me for now) i use it for bowfishing and duck hunting usually 4 or 5 guys and gear bowfishing but only three hunting. was wondering about a gear reduction to help with the heavy load while fishing,how much difference would it make, how much would it cost(havent heard back from go devil yet) and how much top end would i lose when ive only got three guys on board(speed to spare now,im not in a race) or would the money be more wisely spent on engine mods if so which ones.i know these are hard questios to answer but any advice/info would be greatly appreciated. thanks

That is a heavy load 4-5 guys.. For any boat. i suggest you tell your buddies to buy themselves a boat!

Usually gear reduction is used to manage/balance RPM (i.e. take RPM down if you are up on a rev limiter like going from 1:1.31 to a 1:1.26). The higher the ratio, the better your hole shot (1:1.5 better than 1:1.35 for that type of load - not sure what your options are on a GD). If you are running 4-5 guys then you need to look at adding HP and torque to the motor, get the motor done (and associated RPM increase) and then see if you need to adjust RPM.