IMHO, the key is to bear in mind that most of what you fret and stew about before leaving doesn't really matter much in the end. There's way too much to do anyway, and unless you're superhuman in a variety of respects (organizational skills, multipath tracking of issues and information, methodical resolution of an endless list of tasks) you'll never get it all done....or alternatively you'll never actually leave because you're not yet ready.

You're never fully ready. In the end, you just leave.

I fully intended to have a GPS on my bike for this trip (after getting lost in various Italian cities in the dark during rush hour on my last trip, looking for hostels which I hardly ever found). I didn't get around to it. Everyone riding my model of bike says you can't possibly survive without suspension upgrades; I never got around to this, either, and am still on my original shock and spring at 80,000 miles. People said the same thing about the seat, and in the end I agreed--so I bought an Airhawk in Europe and have used it for the past 55,000 miles.

In other words, do what you can and/or feel like, then take off without regrets. It'll be fine. Most of it doesn't really matter--it just seems to matter when all you've got to occupy your time is hanging out on websites with lots of people who think it matters.

One contrary note: there are a few things which actually do matter. On my bike, the doohickey is one such item. Concentrate on these sorts of issues as a first priority, because unlike improved brakes, re-jetting for marginal increases in horsepower, or specifics of tire choice or clothing brands (or whatever), they can ruin your trip.

Hope that's helpful. I'd hate to be thought of as one of those people who "forget what it was like "before the first time" and can sometimes be a bit blase...." I haven't forgotten; I'm just smarter now than then, and I'd like others to benefit.

Mark

(from steamy Belem, soon to cross the Amazon on my way homeward)