like the old ones, there will be a large threaded thing like the end of a bolt sticking out the top. about .5" in dia. this has a recess in the end to take an allen wrench, maybe about 8mm. then there is a large nut that locks the threaded shaft in place. loosen the large nut (maybe is 19mm or 17mm), and turn the threaded shaft anti clockwise to tighten. then do as stated in above post. the old rb boxes will adjust up with even 200k on them.

i once replaced one with a rebuilt and it was not smooth... took a couple of years to wear it in. after that i made sure to adjust as much as possible.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.