the type4 flywheel needs to have a bering pressed in the center to mate with the type1 tranny, and depending on what year of tranny you're going to use you may have to do some grinding for clearance. use a 12 volt starter and everything should mesh.
keep in mind that I'm using a porsche 5 speed on my bug so I haven't done this myself. there's plenty of sources on the net telling you exactly which parts work best (there are several sizes of type4 flywheels, and several sizes work, but one size works best, you can even use a type 1 clutch)
VB