Well, I bought a cart. I did my best to figure out what MSRP really was and offered 10% off. They took it right away, so now I assume I blew it. But I did a lot better than their nutty original quotations.
I used to be the guy who sat in the dealership for hours and tormented salespeople to squeeze out the last dollar, but these days, I don't feel like I have to have the best deal in the universe. God has been generous to me, so if other people make a little money off of me, fine. I just don't want to be the guy who goes in and jumps at the first fake discount they offer.
I have some helpful info for other people, because it appears to be impossible to figure out what dealers pay, and even calculating MSRP is an art.
First, don't even consider buying the premium trim if you have a choice. All you really get are overpriced, fragile aluminum wheels which you don't want. Premium comes with a sprayed bed, which you want, plus the fancy wheels and some body color options. Some dealers will order standard jobs with steel wheels and sprayed beds, so that's what you want.
Second, you want the straight shift, and in my case, the dealer already had it installed on his standard carts.
Third, the rest of the junk the site mentions can be installed later at home, so there is no point in buying it up front because you're afraid you'll get a cart that lacks important features.