I did this in a rental VW several years ago, standard shift. I was grateful for the freedom, but it definitely added stress. I had access to an old mail jeep I was able to practice in prior to leaving.

Yes, roundabouts are the most challenging. My prayer life improved quickly.

Do try to head directly for an interstate or area where there isn't much traffic to practice a bit. If you have a passenger, that should help tremendously with watching and reading maps (I didn't).

After getting home, jet lagged, driving out of the airport, I was on the wrong side of the road. Our friendly PHX drivers quickly notified me of the error of my ways.

JP