I need to order an adaptor for my fuel rail for my FPR, and I've been looking at Sard ones on RHDJapan. Problem is they seem to make 6 different ones and I have no idea which I'll need. The FPR I have is a Nismo one with -6 threads on it, if that's any help. Here's pics of the ones they do, the 4th pic is available as 3 different thread sizes, adding to my confusion:



