I think your best option would be to go to your local Chrylser dealer, sit down with the sales manager and discuss your needs. They might be able to point you to an import agency, or they may be able to do it themselves. http://www.chrylserjeep.co.uk has a handy dealer locator in case you don't know where your nearest one is.
I dont think the size is going to be a problem. Dont forget that Jaguar, Range Rover, Rolls Royce and Bentley are all British names.
The biggest issue will be having the steering wheel on the wrong side. It may not seem much of a problem to drivers in the US, but in the UK the driving style is different, and passing on single lane roads is commonplace. Having to get most of the car out on the wrong side of the road in order to see can be a bit nerve racking.
If you're in the military stationed overseas you can have your car shipped. There's only two people on this board I can think of that have there Treps overseas. Gunslinger here in Germany and AccordKiller in Italy. I'd have mine here in Germany with me, but couldn't do it because of finance issues. I'm paying for the car, but as far as the bank and everyone else is concerned it's my mom's car. I really wish I had it here too. It'd be fun trying to run on the Autobahn with the Volvos, Bimmers, and Benzes. It would certainly be better than the Opel Kadett I had and the Audio 80 I have now. Can't beat free cars though.
Having a left hand drive (or as we Brit's call 'em - Wrong Hand Drive) car here in the UK can be a pain at times.
The most annoying things will be paying tolls, going through drive-thru area's (McDonalds etc).
I do most of my car driving on bigger roads anyway, so the overtaking issue isn't as bad for me. Plus I have a motorcycle for my r&r driving around.
I just love the 'Trep's though. I travel to the USA often, and I normally hire one. Have had one in LA, NYC and New Orleans (navigating it around the French Quarter was fun at times!), and have had several in San Francisco. For some reason, Thrifty seems only to have Gold ones!