corvette triple cone syncronizers
Are you starting w/ an 02 Z28 or Z06 by chance?
Billet keys can be used, yes.
You might want to go into what tests you have done.
For simplicity's sake:
The 02 Z28 has double friction surface 1st/2nd and single friction 3/4, 5/6 and Rev.
The 04 GTO has triple friction surface 1st/2nd and double friction 3/4, 5/6 and single fric. Rev.
The input shaft, all forward gears & synchros and the mainshaft are different to change an 02 Z28 to a triple/double style trans. In short, locating a GTO box, swapping the offset shift lever and putting it in an 02 Z28 and selling the original is the most cost effective. But, that changes you to the M12 gear ratios which you may or may not want.
An MM6 gear ratio F-body/GTO style triple/double box was not produced so it's a custom build.






