In addition to the basic routine maintanance work others have suggested, I would also recommend toting some basic parts just in case... The biggies being (if possible) a fuel pump and a distributor...complete with points, cap, rotor, condenser, plug wires. These two parts can go at any time, and strand you if they do. And often finding parts on teh road ain't all that easy. Furthurmore, if they do fail, each only takes about 5 minutes or less to swap.

Other things to bring... A water pump ain't a bad idea, but not so easy to change on teh roadside. And other basic stuff. A fan belt, some fuel line, some duct tape, bailing wire, tune up parts (which would hopefully be attached to your spare distributor), a coil ain't a bad idea either. ....of course a supply of fluids...oil, antifreeze, brake fluid, etc. And a small assortment of tools appropriate to fix that what you are prepared to fix on the road.

Of course, if there is a problem, it will be something you aren't prepared to fix. That's just the way it is. So...the better prepared you are, the less likely it is that anything will break.

Another quick thing to do before you go that I didn't see mentioned... Lube that distributor. It is often overlooked, it only takes a second, and it will make the distrubutor last much, much longer...if not forever. There should be a little oil cap on the side. Rotate the cap till teh holes line up, and put a few drops of oil in there. Then remove the rotor and put a few drops of oil on the felt below it. Not too much though. If you get too much oil in the fixins, it can mess up you spark sort of like having water in there.

A few years ago, I bought a very low mileage '84 244 with overdrive just a few days before departing on a 2000+ mile trip. But I still opted to take my high mileage '65 1800s...not because it was less comfortable on the highway, nor because it was less reliable...but because I knew full well that if there was a problem, I could surely fix anything that broke. Of course, nothing did...and I've taken that 1800 on half a dozen similar trips since I got it. And never had a problem.

Good luck...not that you will need it. And have a safe trip.

-Matt B
65 1800s 750k+
71 145s 107k!
72 164e ~250k
and other silly stuff