Others will have to share with you David but On the IM web site there are some ACooled docs on my 2110cc from CB is was like
001” and a .002”
I think in the end CB recommends like 0.000 which was like the feeler moves if you can find it...
Here is from the docs.
" For all 1600 cc motors and 2000 cc as well as 2100 cc motors equipped with aluminum push rods you will need a .004” and a .005” feeler gauge. For recent 2000 cc 2100 cc motors equipped with chrome molly steel push rods you will need .001” and a .002” feeler gauge. Check the specifications sheet on your specific vehicle for proper clearance. If not available, remove rocker assembly and establish push rod material prior to adjusting.