Mccadamsoday,
I am currently in the process of restoring a 1982 AMF Sunbird, and there are hairline cracks all over it; this is no major problem for me, however, as the cracking is only as deep as the gelcoat surface. I assume your stress cracks are the same, so this inconvenience should be a relatively easy fix for you!
The easiest and most efficient way to get rid of those cracks is to take filler putty used for fiberglass reconstruction and press it into the cracks with a pain spreader. After the putty dries, sand the worked area down to get rid of any uneven or rough surfaces. The putty will most likely be a different color than the fiberglass surrounding the area, so you may want to paint or spray it over with gelcoat. If the cracks are on a textured or nonskid surface, then you'll have to either replace the nonskid tape, or put nonskid adhesive on the whole area if the texture was part of the production mold. I hope this helps!
God Bless,
S.S.