Make sure you have your GDLT serial number ready when you call godevil they won't even talk to you unless you have an original serial number.
I just went through the same thing. I got an older LT frame for cheap and put a 11hp honda motor on it. I ran into some problems with the prop size and such and was unable to get much info from godevil. I ended up selling the thing just to get out from under it. The motor would only go 4-5 MPH on my 14' jon boat it sucked.
You might want to go over to MUDMOTORTALK.com and ask those guys.