A friend of mine who is a motorcycle mechanic fixed my headbolt problems! he went to hardware store and bought 4 quality bolts with heads on them and washers and just torqued them straight down and it works great!!no acorn nuts or nuts and all!!
some folks are better at measuring than others, and for those blind holes, size matters.
ack! between nutless studs and blind holes etc. I may have moved this out of family freindly.
anyway, my experiences with these engines would indicate, DO NOT take those bolts in/out (!) too many times, the holes seem prone to wearing out (stripping)