Like everything else, "there's a procdeure for that". I've got my owm process that I've used very successfully for 50-something years, but you'll find all sorts of "expert" advice on how to adjust valves. Yes, the feeler gauge is used, but there's a shortcut to get in the ballpark for waking up an engine that is "close enough". Just under your username at the top of the page, there's a small magnifying glass icon. Click on that, and search for "companion cylinder valve adjustment". (Yes, use the quotation marks) It uses a procedure similar to the one we tried during that marathon phone call, watching the valve springs move. to find top dead center of the #1 cylinder.
Jerry
