Welcome to the site, good to have you here. First let me say that when searching and diagnosing a problem "rednecking" to a solution just won't get it done. You can pickup a "in-expensive" timing light - even at most pawn shops or used tool shops, while there get a vacuum gauge as well, these 2 can tell you so many things with your engine. And while I'm thinking about it - grab a compression gauge too.. you can live without it for now.. but it could be helpful later!

There are probably 40 or 50 ways to adjust a chevy rocker. I can't say I've ever heard of the process you used. I'll let Glenn or TechInspector pass on their knowledge/experience on that topic.

So - welcome aboard, with some basic tooling I'm sure "we'll" get to the bottom of what ails your motor.