MIMF

I just used the router to clean up the binding edges of the plastic end trim. Things went bad!
My first guitar; and I could use any suggestions on how to proceed!

PS seems the router bearing melted the plastic and burrowed into everything.
..Tape added to bearing to get size I wanted.

Replacing the plastic end trim seems like a good option.

It looks like the purfling line has minimal damage and that is what will be visible. Agreed; new end trim. If the back bindings aren't in yet then it's easier. When I mess up a purfling line I'll simply make another cut and add another line or two. As long as there is enough support from the linings inside it's just a matter of esthetics.

Those were my thoughts exactly. I can't tell for sure but it looks like all the rebates are cut and the back binding is not in yet. I would get the ledges as clean as possible then remove the tail graft. Make a new one and wedge it in. Then just clean it up by hand to match the rest of the edges.

It's apparent that your bearing is not moving free enough to keep up with the router bit speed.

The bearing spinning with the shank, as I was using router VERY lightly.... Not pressing bearing against side walls. Then the spinning bearing, wrapped with tape suddenly turned white (with melted plastic). I had a piece of tape wrapped around the bearing to get the right depth.. I assume the tape probably added to the friction.
Live to Learn!
Hope I can fix this!

Replace the end graft, and build out the binding rabbet, and you should be good to go. It's lucky that the purfling ledge wasn't trashed.

You probably ought to get a new bearing unless you can prove to yourself that it really does spin freely.

I use the same method as you do, including the tape to adjust the cut.

I cut the tape askew on the bearing to make sure there isn't a lump in one spot that will transfer the irregularity to the cut.

The bearing is a guide and is pressed up against the sides and doesn't spin. It will "read" any dip or bump so a true surface is essential.

Not pressing the bearing against the side hard enough to keep it from spinning with the bit can be a problem. Assuming your bearing is greased properly and the bit spins freely then you should put enough pressure against the side so the bearing "rolls" while the cutter "spins".

I would also recommend instead of the tape on the bearing, put the tape on the guitar where the bearing will ride when you recut the replacement tail graft. That will "shim" your bearing out the same distance that tape on the bearing would, without all the hazards that tape on the bearing risks. That would also protect your plastic insert from friction from any bearing spin (which as mentioned above by Clay you don't want in the first place)

I will frequently do this for a first cut with a router even when the bearing is the size I want, in order to hog off most of the cut, and then take the tape off and redo the cut so that this final cut is only cutting the thickness left from the taped cut.