When I moved from Minnesota to England I never had a problem driving on the wrong side of the road because you're in good company. The hardest thing was looking in the rear-view mirror. I kept wanting to glance to my right.
I do not find driving a L.H. Plymouth in England difficult. Its kinda like being home.
I did have one incident in England where I got into the car to go someplace. When I put my seatbelt on I excitedly said, "Where's the steering wheel"!? Oh, that's right it's L.H. drive, Stupid boy!"