They used Rivet Nuts for the console and the duel exhaust hanger for the passenger side.
Here is a kit that Firebird central has, or you can get your own rivet nut.
http://www.firebirdcentral.com/1967_1969_Firebird_Console_Floor_Mounting_Set_p/con-57.htmhttps://www.fastenal.com/products/fasteners/riveting-self-clinching-products/rivet-nuts;jsessionid=F1DE58A4FB6846A97B106FDB6271E210.jvm2?r=~%7Ccategoryl1:%22600000%20Fasteners%22%7C~%20~%7Ccategoryl2:%22600191%20Riveting%209and%20Self-Clinching%20Products%22%7C~%20~%7Ccategoryl3:%22602457%20Rivet%20Nuts%22%7C~
It takes the right tool to compress those. I tried making a tool but end up having to purchase one. Some info on my sight.
http://www.firebird400ho.com/rivet-nuts/
