Clutch question

[Bernie]

I have a K20 with a 350 and a 4 speed. The clutch works with a length of threaded rod that goes through a small casting that goes against the arm that works the throwout bearing. I keep on breaking the casting. I've bought two from LMC truck and just broke the second tonight. They broke where the rod goes through the casting. What do you guys use ? Maybe I was just unlucky with the LMC quality. I seem to remember that these were sold for 2wd trucks but I thought that the only difference was in the length of rod.