Stupid me...new floor pan in my b body and all mounting holes for the seat belts were in the new pan. Or at least I assumed...finished up the interior, installed seats and mounted the rear seatbelts, then got to the front and mounted the floor tunnel-lap belts. Went to mount the retractors on either side of the bench seat and alas, no holes...should have noticed before but didn't.
What are my options? I've done a search and there's mounting kits that use nuts/bolts and backers that look fairly easy to install, but is that a good idea?
Any help is appreciated!
Thanks.

What car ? I'm pretty sure the seat belt nut plates for the outer belts are in the rockers so all you would need to do is get some measurements and drill holes to get to the threaded holes .

This is a 68 b body. It should be the same.
I would maybe use a hole saw and then the pilot bit will go through the hole and the hole saw part can be stopped as soon as it goes through the floor pan.

One more.

Awesome! That helps a BUNCH....
Thanks for the reply JohnRR and thanks a TON for the pics bboogieart, I should be good to go!