Hey guys i need some guidence here. I'm building a 512 and was talked into switching to a roller cam not realizing what all was involved in doing that, I bought a Howards 565 lift hydraulic roller can and i ordered 1.5 Harland Sharp Roller rockers. I need to figure out pushrod length and i have no clue how to go about it. from what i understand you have to have an adjustable pushrod tool right? Well it looks like there is different lengths? How do i figure all this out. This roller can stuff is all new to me. I've been running a 292 purple shaft for 30 years. Im an old school guy and just sticks with what works. Any help would be greatly appreciated. The pushrods are the only thing left before i can finish the motor. Anyone? I'm an old school guy and don't like change and man have i paid for it...lol