the mast pan should clear a 4" stroke crankshaft. it also has more room for the tru turn setup. the holley -1 clears a 4 stroke but the -2 does not. to get the -2 to clear you have to mod the front of the pan like
http://ls1tech.com/forums/conversion...ts-info-9.html
post 163
a autokraft pan might clear the holley setup but i have not read about anyone using it with there kit. you could try it. to me it looks like it would work