Backseat Install

I'm installing the backseat in my Demon.. I know it hooks in at the top, but at the bottom there are two seat frame "brackets" with what look like holes for attachment...and they're centered with holes in the floor pan, however they're a good 2" to 3" above the floor holes.
It's been 2 1/2 years since I pulled the old one out and I don't remember having to unbolt anything there.. Do they fasten there..? Long bolts..? A "j" hook style perhaps..?
Any help would be appreciated..!

Thanks,
John