i have not seen a bike yet that didn't need some minor modifications. it should fit fine with them. most of us got our bicycles from wally world or one of the marts. it awesome to take a inexpensive cruiser and turning it into a motorized bicycle
You'll need the larger frame adapter. I wouldn't drill the frame. I have the same bike. Reinforce the front fender, mine started cracking within a week of mounting the motor. Other than that it's a easy build.
Kings 70cc 3200+ miles. Now on a Schwinn Point Beach NOW in mothballs..