Checking for rust … common areas?

So I've found what looks like a solid, driver condition '73 Valiant that I'm quite interested in. I've asked the seller about providing photos of the frame rails at the upper control arm mounts, rear quarters/inner fenders, floorboards and trunk floor.

She will be able to get photos of everything but the floor (carpeted), but did check under the car for rust when she bought it. Which leaves me with a couple of questions for those who know more than I…

1. What's involved in looking under the carpet at the pedals? I'd like to make a suggestion on easily checking if possible. Or maybe have a local FABO member give the car a once over?

2. Are there any other places to check for terminal rust?

The seller's daughter is currently driving the car, so it's at least got that much reliability going for it. I'd check in person, but it's almost 800 miles away.