There are several ways of installing the fin boxes in a surf board. Most conventional construction had the board glassed first and then the fin box holes routed in. With this method of construction, however, routing out the fin boxes is very messy work and potentially requires some additional work. So, I like to do it before glassing and just make sure to tape off the holes in the fin boxes and cut the glass / resin off when it has not totally hardened.
The fin boxes I am using are:
1 - 8.5" Fins Unlimited box
4 - FCS Fusion fin boxes
I also chose to do all the hardware in white for contrast.
Fin boxes routed:
Me covered in sawdust from the router: