Is this the 2-man or 4-man bulkhead?
Appears to be in the parts manual - this is the front (2-man) bulkhead, which I believe matches your picture - See TM-92320-280-24P-1.
Look for Figure 209 - Cargo Bulkhead and Mounting Hardware. Bracket is #11.. the bolt into the floor is #15, with #14 and 13.. while the other side of the bracket is a bolt that goes up to a cargo hook and then washers/nut.. This is the front (2-man) bulkhead, which I believe matches your picture.
The one that goes into the floor should already have a threaded insert into the floor (or at least did in my experience).
#15 - SCREW,CAP,HEXAGON H 1/2-13 X 1.50
#14 - WASHER, LOCK 1/2
#13 - WASHER, FLAT 1/2