THANX all for the replies- I doubt the factory would try to hold wood down
with rivets, that won't last long.  And these rivets aare in a straight
line, in my 71 single cab they weren't in line.
>Doug:  You could countersink the holes in the bed and use the flat head
sealing
rivet to maintain a flush finish. btw.

now THAT sounds like an idea to try
THANX
ed