When I started stripping my TCS, I swore off Bondo, and scraped off literal pounds of it from various bad PO repairs. I mixed milled glass fibers into resin for a more fiberglass filler, which works great. Then I found Bondo Glass, which is resin with milled fibers already mixed correctly. The stuff also works great, sands easily, cures in 30 minutes, so I can continue the same day. But, I haven’t painted it and lived with it. Does it crack off if the body is bumped by a cluefor’s door for instance? So, for more exposed repairs, I covered the BGlass repair area with veil, as a more continuous sheet of glass. For your over gel coated edges, you might Bondo Glass, then cover with veil.
I also found a grey layer that laughed at the Safest Stripper. I think it was something Lotus used, but never identified it.