Does anyone sell the inner fenderwells with the seals already stapled and attached for a 72? If not, how do you staple the seals to the plastic?

 

The fender well seals usually are shipped with the required staples.

 

You have to line up the holes and manually insert each staples through both then bend them over and hammer/dolly them flat.

 

There may not be holes and if there are dimples, they may not be in the right spot. Lay the seals out on the inner fender to check. I replaced some years ago and had to drill my own pilot holes in the correct spot for the staples.

 

If you use the thick staples supplied with the seals then you'll need to drill holes in new plastic inner wells.
On this latest go-around I just used a normal T50 staple gun. Held cardboard over the other side to catch the staple then folded the ends over. Not "correct" but much easier and I put several extra staples in there. My last set of flaps were also too small causing them to tear, so I cut a set out of masticated rubber.

 

I made staples out of tinned copper wire that was the same gage as the supplied staples. I placed them through small holes I drilled in the rubber, using the inner fender holes as a guide.

It was much easier to crimp them than the steel staples. There's no corrosion and all is still in place, looking good, 20 years later.

 

I taped the new flap to the fender liner with blue painters tape, then with a 1/16" drill bit, I carefully drilled through the rubber flaps using the existing holed in the plastic fender liner. My kit did not have enough staples so I had to reach out to the manufacturer and they sent me some more. I like VC455's tinned copper suggestion as the staples in my kit were very brittle and several staples broke when folding them into position.

Rodney

 

They shorted me on the staples as well and refused to send more.
I ended up buying https://www.ebay.com/itm/331848209319 and paying the 10 bucks shipping for probably less than a buck to send them