97 Dodge Ram Van, rear bench seat belt bolts cut

A previous owner removed the rear seat. The positions where the seat and seat belts attach near the walls he unbolted. The two middle positions, below the seat where the other ends of the seat belts attach, are odd. Instead of a bolt hole with a bolt from above, there is a metal plate/flange below the carpet that runs to the rear corner, and where the seatbelts attach there is an upward pointing bolt that he cut off. I need to figure out how to get that cut bolt out and replace it. Help?

I'd try a set of easy outs/ bolt extractors

They look like the image I googled

http://www.team.net/www/morgan/tech/tools/part1/2-EZout.jpg