02 speedster 160 single front seat redo

[josh_44_44]

I have a speedster 160 and I need to redo the front seat the backrest is easy to remove but the bottom seems to be be riveted on each side and possibly on the bottom getting it out is ganna be easy but how do i go about reinstalling it after I recover it since there is only one cup holder on the right side and no other access to get rivets back into it to hold it???????

thanks