Removed epoxy, broken guide feet, and thread to the end of the wraps. The area under those wraps is matte. Appears the whole blank was finished (glossy), so there is a significant build up of epoxy which averages up to where the old wrap began. Should I just leave that alone, wrap the new guide filling the space that has the matte finish, and overlap the new epoxy over the old? Or wetsand the high spots before wrapping?

If its a very light rod like a fly rod or steelhead rod you need to be really carefull but if it a regular surf or boat rod you should just try to start the new wrap right where the edge is on one side and end it right where the edge is on the other side. It sounds so exact but in fact its easy. When you apply the finish let the new finish just slightly go over the gloss part of the rod. I'm only talking about 1/32 overlap with the finish past the ends of the thread up on to the gloss part. it will level out and this way you will completely eliminate that interface between the gloss and the matte parts. This is pretty much how you would replace a guide even if the glossy/matte problem didn't exist.

Thanks Mike. It is a boat rod. The edge is very defined, by the last thread wraps as they came off. I am planning to make sure the new thread is saturated before doing the 1/32 overlap.

Don't worry , it will come out looking good.