u/Jamesotty

I'm just recently learning about crank end play and how there is a shim stack up behind the flywheel. I tested my engine and I do have a small clunk I was thinking about just ordering a set of shim's and I already have a new crank seal just to put more shims in and put the new seal in and retorque. Is there anything I should consider while doing this procedure? I was also considering pulling the heads and reseating and adjusting the valves as far as I understand, I only need head bolts to do that job? 1972 1600cc engine with 90,000mi