What's wrong with the pre-cut bodies? Seem to fit very well. One tip is to chop the nose of it off that goes through the front shock tower. If you don't when the chassis flexes on a bad landing it will rip the front off at the body mount hole. With my current body I chopped of the nose and double layered drywall tape and shoe goo on the body mount holes. Seems to be holding up well.

Side note: I do hate the way Losi nitro bodies comes pre-cut. Plenty of people converting the truggy to electric that would prefer the body not to be pre-cut.