Not likely to see any fiberglass strands, unless you're really diggin deep...in which case, you'd be doing more harm than good.
The later cars used what is known as SMC(sheet molded compound), which is not like the older style pressed glass.
Be vewry vewy careful with the razor blade...you CAN create gouges that will require extra bodywork in the end. Also be vewy careful with the heat gun, so that you don't "melt" the panels...they will warp if they get too hot.
Otherwise, it looks like ye off to a good start!
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Joel Adams
C3VR Lifetime Member #56
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"