No one has mentioned that there is a kit from Chrysler to add the second armrest to the 2001 passenger seat.
It's detailed in the guide at
www.ptdiy.net
I'm the guy who got the parts together and wrote the guide. Since then, Chrysler has packaged the kit through
www.ptdiy.net
I've added the passenger armrest to over a dozen local 2001 PTs.
It takes about 1/2 hour to remove the seat and add the brackets and hardware.