Suburban rear seats and tracks, any info?

[aerotruk63]

In the Province where I live we have a strong car/truck culture. The problem is a language barrier. I've known this guy for 25+ years but he doesn't speak a word of English. He's French Canadian like me so we'll refer to him as Frenchie. So I'm asking you guys for help.

He has a radical bagged American Built 65 GMC Suburban V6 without any rear seats. He needs the seats so he can bring his kid's with him to the shows, not the wife cause she divorced him years ago over his passion for these truck's. He also has a 66 pickup with a 502 in it.
Now in my search for seats for his truck we've come across that there may be two types of mounts? He has tracks on his rear floor and there was apparently some years without tracks. In all my literature I have no pictures of these tracks so I'm looking to find out how the rear seats were attached to the floor! Are the rear seats interchangeable between 60-66. What years do interchange?

Now as for pictures of his trucks, if I had any to show you guys I would. I know, I know, but I'll get you some when I get home for the winter. Still out on the road!

Hey, Thanks for any info you can share.

From 1963 Chevrolet Truck Data Book.