I have two of the MattK underseat sub boxes. They are awesome and the driver's side one fit fine. However I have a 2007 JKU and Jeep put load cells between the brackets and the seat slide rails in 2007 only. So the brackets are shorter to make up for the difference that the load cells add to the height.
I want to order the 2008 passenger side seat brackets from a 4 dr JKU and swap them out. To ensure I get the right ones I need the last 8 digits of a VIN from a 2008 4dr JKU. Preferably one that has already installed the MattK sub so there's no doubt it fits. Any 08 4 dr should work though.
If anyone is willing to PM my a VIN, I'd be very grateful. I really want to get both subs in.