I purchased a new 2008 TRV, then found a very cheap rear trunk. I purchased a new 09 rear extension rack and put everything together tonight. But ther rear seatback does not go all the way to the top of the trunk. Also it looks like there are holes on the trunk to mount a seatback, so what should I be loking for here? It works as is, but looks like I am missing something and a taller rear seatback prob would be nice for the wife.

 

If I understand this correctly, you bought a TRV rear "cruiser" box? ($389) NOT the rear cargo box ($379) for single quads? (different part#'s as well)

I'm looking at the '09-'10 AC accessory catalog and it appears to me that the TRV "cruiser" box sit up tight against the back seat rest of the 2-Up seat that came with the TRV. It shouldn't have any padded cover, cause there's no room for it against the 2-Up seat.

........NOT MINE.........


BUT the rear cargo box for regular quads DOES (thus the holes) and requires AC's SPDrk quick attach kit to mount to the rear rack.

In general they are identical cargo box's. But both mount differently due to the style of machine.

Now I'm just looking at pictures, but there's ALSO the possibility that you have to "dismantle" your 2-Up seat and remove the backrest (that makes no sense to me) and use the upright pad that's supposed to attach to the cargo box?

That's all I can offer. But note that the rear cargo box is NOT known for being very durable or waterproof. Lost of various posts floating around complaining about it, cause I was looking VERY hard at "upgrading" my '08 TRV to a "cruiser" as well last summer.
I do know that AC offers a liner bag now for the waterproof issue #1436-266 ($56)

Good luck!

 

by looking at you pix it is obvious to me I need to get a diff seatback. Yours is taller and fits "into" the back of the box much better than mine does. As I said it works as is, but just looks a little off. Now to find AC lime green paint as it was not the correct color. But for $20 bucks off ebay I had to jump on it.