[95blkmax]

There is no "list" for this kind of stuff. Most dealerships are individually-owned franchises with a few corporate-owned. It is fully up to the individual location if they want to accept a particular credit card, or if they want to set whatever limits they want.

Your best bet would be to literally sit and call dealerships in your area and ask that question to either the sales managers or GMs. I'm sure if you speak to a random sales person they may tell you yes just to bring you in the door and then "find out they don't accept AmEx anymore". So you definitely want to get that confirmation from a higher up