I have a couple of motors, and having just gotten my H16, I have yet to try them out. I have a 2.5 Merc that weighs 29 lbs. with built in tank, and a 9.9 Gamefisher that weighs 65 lbs, and has a 10 gal detached gas tank.
I have learned a few lessons the hard way re boat motors. The 2.5 would have no problem moving the H16 at 5 kts. I had it on a 17 ft mono hull and have been to the marina where you can see lots of them used as kickers. How fast do you want to motor?
My first motor mount made out of oak, was broken by the little motor and boat trying to go opposite directions at the same time. The lesson was that there is alot of force involved in moving even a 16 ft boat. So any mount that you make, needs to be very strong so that you don't tear up your boat, motor, or yourself ! Even with a small motor.
Secondly the motor weight becomes detrimental as the motor gets larger. The size that you are talking about, could weigh quite a bit. I would do some checking with adding weights to the back of the tramp, or even further back. Temporarily put a 2x8 across the hulls, where you would likely hang the motor, and add the weight. Add your weight as if you were at the helm, and then check your balance.
After this is all set up, remember that the torque of the motor is going to try to fishtale the boat and go over backwards. If your balance is very far off, you could have the boat flip over backwards with you eating the propeller. Not good! And righting the boat with the motor attached is a gamble!
Go slow and careful with the experimenting. If it works, let me know how the bigger motor works, and I may try my 9.9 ! Thanks in advance.