I have a 1996 Budget Saleen. It is number 07B. In answer to your question, the bumper number should have a B designation on it to match the under-the-hood plaque. Here is a picture:
These cars are notorious for not having the bumper numbers. The reason is that they have had the front bumpers re-painted numerous times b/c of being hit on parking blocks. Additionally, the magnesium wheels are often in bad shape due to curbing and lack of care when the rental mechanics swapped tires. As you can imagine, most of them have experienced numerous tire changes.
The post above is also correct about the dash plaque. They were not originally installed in the car (high theft item), but were supposed to be delivered to the owners following the auction. You might want to call Saleen to verify that the plaque was delivered. If it was not, they will send it to you. Unfortunately, mine was but it wasn't on the car so I still have to get around to ordering it for the above stated $100.
There were 30 cars produced in 1996 and 88 produced in 1997. The Saleen book talks about others, but that is contradictory to what Liz Saleen told me when I called about it. Most were automatic, however there were a few stick cars (more rare). They were all ordered with the standard Saleen "package", plus light bar and Magnesium wheels.
Here is a picture of what the stock stereo looks like in the car. Unfortunately, swapping back will probably be a really big deal for you. My car didn't have a CD player and I wanted one. When I looked into getting an aftermarket one I found that I was going to have to run all new wires and speakers. The Mach 460 head unit is actually a passive system. There are 4 amps in the car that power the speakers, which means you can't put a powered head unit in the car (powered signal to power amps = bad kimshee

) I ended up going to the junk yard and pulling the wire harness from a car that had a CD player, then purchasing a stock CD player. You can check out my site to see how to do the swap at ml.truckmoxie.com/sal07b
Needless to say, I've pretty much re-done everything on the car. I think it is worth it though b/c it is a limited production inside an already serialized production car. The closest things to these cars are the Shelby GT 350H's. Go and see how much they pull today ($$) compared to the regular GT 350's (not to mention it will be interesting to see what the "new" GT 350H's go for once they hit the auction block) and there were thousands of those (not less than 200). But I'm not biased of course

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