Generation IV Internal Engine - Afr 225 and yella terra 1.7 close to heads /interference?

I was running my afr 225 with 1.8 yella terra non adjustable. They were fine and didn't have any clearance problems. Now switched to 1.7 non adjustable just to make things bit easier on the springs but finding the 1.7 are very close to the heads now and figure might have to clearance the heads or the rockers and don't want to take the heads off now to do that.
Anyone have this problem and how much clearance is minimum?

I had the same problem with my AFR Heads and yellaterra ajustables.

I clearenced the rockers , And also I had to clearence the valve cover spacers too ,

It worked OK for a few months but the yellaterras ajustables are heavy .And noisy.

I ended up upgrading to T&D Shaft 1.7 adjustables , They are light weight and very slimline and have no problems clearing everything.