Your frame looks much like my Mongoose Paver. A HT motor will most likely fit but there's no room for the carb. I'm using a modified CNS carb adapter from Pirate Cycles and some plastic vinyl tubing. The vinyl tubing is not fuel proof but I keep an eye on it , it actually seems to be holding up but if it don't I have another 4 feet of it
The stock mounts should work without much modification. I think you'll need to have a slant plug head, too, but most of the kits come with those now. A lot of times the plug is mounted to the intake side and you'll need to turn it around necessitating a torque wrench, something you'll have to have anyway. A 3/8ths inch beam bar type is sufficient and fairly cheap.
Keep us updated and posting photos