Here’s the Promaster 3rd man seat. Forget about letting the extra rider sit on a bucket or milk crate. This innovative seat fits between the driver and passenger and does not sacrifice any space in the cargo area. The seat attaches to a well designed bracket kit that will install in about 90 minutes. When the seat is unoccupied, the back folds down as an armrest/cupholder. All you need are common home workshop tools to do the job. Ships UPS in 2 boxes.
Requires removal of the armrest on the passenger seat, which is very simple. A cover piece is included in the kit.