TOPIC: mercontrol compatability question

Good evening folks! ok so the 115 hp mercury that came on my boat i recently purchased has turned into a complete nightmare the trigger unit and switchbox are bad my engine is a 71 115 hp mercury, my brother has a 72 mercury 85 hp both are of the thunderbolt line his boat is going to be restored and he has offered to let me use his motor i was wondering if i will have to strip all of his parts to put it on my boat we both have mercontrol throttle box's since my motor is a 71 and his is a 72 will they just swap straight across the only thing is mine has power trim and his is manual what would be the best way to swap motors? and can i use my conrols or will I need his?

direct change same ones.