S&P now has shorty headers for LS motors w/mechanical clutch linkage
I know most of the guys running LS motors are using hydraulic clutch setups, but for simplicity I wanted to use the stock mechanical setup with the Z-bar. I worked long distance with Street & Performance by having them send me tack welded headers that I was able to modify, tack weld the primaries in better locations, and then they designed a jig to match. After a few attempts, they now have something that should clear the stock linkage, as well as the stock steering box very nicely. I worked with Gary in their header department, and if you're planning to go this route, I'd suggest you ask Gary to send you a set in the tack welded version to fit check and be sure it'll work for you, and then return them for final welding and ceramic coating.
I'd seen some inquiries from guys asking if there was such an option available, now there is.