How do I tell if the pushrods are touching the head and need clearancing? I can't see in there very well with the rocker. I've been shining a light from the bottom and doing a weird dance to try seeing all around it but there has to be a better way.

I have an RB with standard port victor heads, Hughes 1.6 rockers and smith brothers 3/8ths pushrods, so far I've done one side and I haven't seen any that looked like they hit but I have read about other peoples issues and I worry I am missing something