RHS flow #'s

Hey Guys,

can anybody tell me which Headbolts you are using with the RHS-Heads?
Tryed to install them today without success!! The original ones are too short.
Only the 2 long Bolts fit, but i need them for all the holes IN the Head.
on the outside the small ones fit, but IN the Head they are too short.
Measured the depth off Head mounted is all holes 4,8" deep.
But i can´t find some screws who fits....

HELP! :(