I forgot about my original box sides that are stuck in a corner waiting to be turned into a trailer some day. Hopefully these dimensions will help you with template placement:
Front of box side to front fender bolt hole in angle strip = 19 1/4"
Rear of box side to rear fender bolt hole in angle strip = 10 1/2"
Distance between holes = 50"
Distance from angle strip (horizontal face) to top (brace) fender hole (vertically)= 10 3/4"
