help replacing 1999 tacoma bench with 1998 60/40 seat

OK help replacing 1999 tacoma bench with 1998 60/40 seat
outside holes line up
inside ones do not - looks like holes line up with pop outs
so how to pop out?
what bolts and nuts to use?
other ones that don't line up put the bolts in from the bottom to plug?
any ideas and help?
thanks

 

the holes are there, just filled with body putty that gets hard like old chewing gum.

use a Phillips screw driver to drill it out safely then run a tap to clean the threads.

as to the old bolt holes, put bolts back in them from the top and buy some for the ones you need or pick them up at the salvage yard