Appbiz.com has a very nice carpet set and was working on a rear seat delete a while back. You have to contact them for the 944 set as it's not listed. They have a few different materials. The felt is very nice and looks very factory 'RS' esque.
You may want to put some type of sound deadening back in around the seats. With the bottom portion of the rear seat removed you will be absolutley amazed at how loud it gets in the car. For track only it's alright but if you do any street driving it's very annoying.. And I like my cars loud!
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