I know having it done right is the way to go. I may eventually have it done correctly, just looking to try to attempt it myself for now and fold the seams since I can't sew lol. I still haven't gone through and serviced the sled yet. I got it running but it needs a little work and I don't want to dump to much into this thing until I know how its going to clean up and everything. It just annoyed me when I hear it cracking as I am sitting on it haha.
For what it is worth, I have an alternate suggestion. Most likely when the seat comes off the mounting bolts/nuts will be worthless and will either break, spin, or break out of the plastic seat base. Others may have different ideas, but one of the best ways to get the seat off with minimal damage is to slide a hacksaw blade beneath the tunnel and the seat and cut the bolt. Once the seat is off you can see better how to restore the blind nut in the seat base.
OK, with that said, save the old seat for proper fixing. Cut a new seat platform out of plywood and pick up a piece of foam at the local fabric shop and make your new temporary seat. Attach that one any way you want, "tee" nuts or drywall screws. Then take your time and get the real seat fixed properly.
And, with that said, an alternate mounting method for the rear end of the seat is to drill a hole through the glove box hinge and use a pair of 1/4 - 20 x 1 cap screws. We have found that this is far easier than trying to patch up a broken rear corner of the seat.