"Any suggestions on electric motor,
The boat is 35"×12" "
Sorry, only just picked up on this!
Since no one else answered that question, here's my two €cents worth.
With a 3 to 1 length to beam ration the hull was probably not specifically designed for speed.
More for sea keeping.
So I reckon something like a 540/550 brushed and 30 to 35mm 3 blade prop running on a 7.2V NiMh or 2S LiPo should do nicely for a scale speed.
Alternative; a 28XX brushless around 750 - 1000kV.
A battery of 4000mAh and up and an ESC rated circa 20Amp continuous should give you a running time of an hour or so with little or no risk of anything overheating or need for complicated cooling plumbing👍 If you want more WHOOOOSH try a 10 cell NiMh or 3S LiPo - but keep an eye (finger tip?) on the motor temperature!
Hope this helps as guideline.
Happy restoring/converting. Let us know how you get on 😉
Cheers, Doug 😎