Cold Weather FG Repair

[ksreynolds74]

Two quick questions on a project boat I'm working on:

1. I'll try to get a picture of this one...I'm repairing two failed repair jobs in the bottom of my hull. I have floor & stringers out, so access isn't a problem. The two repair areas are about 24 inches long and 5 inches wide. They are ground out and tapered, and are bisected by the keel. There is about 3-4 inches width of keel. I can NOT get to pink glass. The glass in the keel is all dark, which I assume means its bad. Will the new glass bond to this and cause an issue? If so,I'm laying the holes up with melamine on the back side, so I was thinking of just putting the release wax on the keel (to keep the shape & line), then cutting it out from the bottom, and filling and fairing out from there.

2. What is the coldest temp. you'd recommend doing repairs with polyester resin in?