I have a Mathews UltraLight and have had it long enough that the wooden grip became so loose I had to remove it and reglue it.

Before this I was shooting perfectly. I'm shooting good groups now, although they are down and left. I would assume that would be from changing the grip, so I just plan on re-sighting it in.

However, I'm noticing some fish-tailing at release. Could this be related to the changes in the grip? TIA

It could be because your string has stretched and changed your knocking point. Which in that case you'll have to paper tune it.

Could also be you are torquing it. Pay attention to the grip.

I guess that's what I'm afraid of: that regluing the grip has changed its position enough that I'm torquing it. I'll shoot again tomorrow and pay more attention to that aspect.

could be something hitting your arrow...such as the arrow rest could be slightly out of adjustment...