My drivers side bottom foam was lightly glued to the metal frame and so was the heating element. So I used the clamps to glue the new foam to the metal frame and also needed the glue to tack the heating element to the foam. I could have just laid it on there but I didn't want it to move cause of my weight.
Oh, I see.
When I replaced my seat foam and heater pads, my original seat bottom foam was not held on with any type of adhesive.
The foam was just sitting in the frame.
The original heater pads, both seat bottom and seat back, were held in place on the seat foam with some kind of adhesive.
I just set the new seat bottom foam in it's spot on the seat frame and I placed the heater pads in their spot.
The heater pads each had a slot in them where the Velcro that holds the center seam of the leather seat cover to the seat foam below.
My replacement heater pads came with a double sided sticky tape that allowed you to peel off the paper backing and stick the heater pad to either the foam or the leather, depending on which seat you installed the pad.
I didn't even use that tape since I wanted to be able to remove the pads if they went bad, without messing up the foam.
I'm a good sized fellow (not as good sized as I was back then, thank goodness) and I have not had any of my replacement pads move at all in the years since they were installed.
But, I see where you may have had some concerns.
In this picture, you can see where the original seat back heater pads were attached with some kind of adhesive that tore away some of the seat foam when they were removed.
I wanted to avoid that damage to the foam in the future, if I could.