Yeah heat guns are not trust worthy, when you turn ps3 on does fan kick on for a sec? If so your ylod is prbly the same as mine was. Mine needed to be reballed/reflow cause the cheap ass solder $ony used broke and there cheap thermal paste was drying up bad.
Repair shop fixed all that, my suggestion would be just to take it into a local shop if u can find one cause most time they do it in same day.
Much safer then trying yourself especially since u said your technology impaired LOL
"Snake. We're not tools of the government, or anyone else. Fighting was the only thing... the only thing I was good at. But... at least I always fought for what I believed in." - Gray Fox