: I would strongly suggest doing a seal coat before using an epoxy based
: filler. The epoxy will soak into the surrounding wood and the color will
: not quite match the rest when you get to glassing.

I have a question about the above statement. If you were to apply the gap filler first and it colored the surrounding area a little, then if you applied a seal coat later - wouldn't it finish coloring all the wood to match?
I ask because I'd like to use an epoxy based gap filler now but would like to wait to apply the seal coat until just before I am ready to glass for less sanding and better bonding. I suppose that I could wait to fill the gaps until I was ready to glass but I'd kinda like to get them hidden from view (this project is getting a lot of attention).