any suggestions for custon bucket setup in 1979 GMC sierra1500 4x4

Im trying to put bucket seats in my gmc sierra, the floor rises to the right height on the outsides, but on the inside the floor drops befor the tranny hump and i can't seem to settle on any ideas for bolting the inside brackets of the bucket seats. oem full bench seat only require 2 bolts on on the driver side and 2 bolts on passenger side, anyone have any ideas, there's no place to bolt the inside brackets and then there's the hieght problem.

thanks

Dave