most people make their own filters by cutting down a furnace one as the factory ones are a bit pricey.
Here is the factory install info from the Scoobytruck library - http://www.scoobytruck.com/pdf/Baja-cab ... er-kit.pdf
Thank you for the instruction. I just bought the 03 Baja, and I don't have much info on it. The owner manual doesn't come with it. It is a little tougher than the Toyota and Audi. Audi is the easiest one to replace the cabin filter. It is in a very convenience place under the hood by the windshield.
I saw several cabin filters on eBay for the 03 Baja, and the price is reasonable.
Enjoy you new truck and if you have any more questions go ahead and ask or check out the library for a lot of good info - http://www.scoobytruck.com/lib.html