Well after reviewing this I went to Home Depot and found some PVC connectors in the plumbing area that I thought might work as well or even better. I found the sizes I needed and drilled a hole through it at the right height and then with a Dremel, cut a slot so the detector can lay flat if needed.
Next I took a sander and sanded the old “mouse ears” down until they were flat and to rough up the surface to help the adhesives hold. Likewise I sanded the bottom of the PVC connector. First I applied the PVC primer to both pieces and then the pvc glue and set the pieces in the proper position.
I let it set overnight.
I got some nylon washers and filled in the gaps when the shaft and bolt were applied. I also used some gasket making materials if needed to get it nice and tight. I also found a gasket compound and again filled any gaps. A little paint and I’m back in business. I’ve done 3 so far. Total cost per coil was $5/$6 each.