I flew to Little Rock, bought it, and drove it back to Dallas. Here's how it went.
1. Dealer put a temp tag on it that was good for about six weeks, plenty time to register it in Texas. Sounds like you're buying from an individual so I know this doesn't help much. My guess is you'll get a temp tag when you transfer title at the FL DMV.
2. I called my insurance company while closing the deal and started coverage effective immediately.
3. I paid no sales tax in Arkansas. Paid it in Texas at registration. Too bad. Lower rate there.
4. That's all I've got.