normaly it will between the valve and follower, but there are exeptions, like pintos, but you cant very well measuese between cam and follower on a v engine, follow what the maker recomends, as the gap will be different for either
On OHV maybe between stem and follower; on most OHC/DOHC engines between cam lobe and follower, most OHC designs will only allow that sort of check as the bucket completely encloses the valve stem.