An auto dealer, of any kind (wholesale, retail, new, used, broker) can accept BTC if they choose too.
The real issue is the volatility of BTC. Will the value fall so fast that the dealer can't buy new goods or pay vendors?
If you want anonymity, that's never going to happen through a dealer, because they need the new owner's info to transfer the title.
I'm a few weeks from getting my wholesale California dealer license, and I also have my own development team, and would be happy to create a BTC payment service if enough people are interested.
The only way I could see it working, though, is if the price volatility is mitigated through a fixed or percentage-based transaction fee, or by designating a "basement price".
In other words, if the price has ranged from $1900/BTC to $2600/BTC over the past week, the $1900/BTC value would be accepted for the transaction.
This is important because, although the BTC transaction may only take a few hours to validate, the dealer would still need to convert it to cash through a service like Coinbase. This could take a week, which, in this speculative case of a $700/BTC price swing, could mean a big loss. Especially for larger purchases.
In any case, I can put up a Google Form to collect names of those who might be interested. But, I can't sell anything legally until my licensing is complete.
http://mwrightmotors.com/