I am in the process of cleaning up this little 70 and the rear fender is cracked all over. There is a chunk missing off one corner but I plan to smooth it and remove the same amount from the other corner to even it up. So far I used some adhesive to align the cracks abd put a 1/16" - 1/8" groove into the crack line on the top side. I am thinking either use fiberglass to fill and sand, or possibly melting some plastic into the grooves. I will do the underside this way as well. Any recommendations...besides just replace it? Thanks