I've removed my Xtracycle from my Trek 520 to an old Gary Fisher mountain bike. The transition has not been easy. I got rid of the stock suspended fork and replaced it with a Surly 1x1 fork. I have to build a new 700c wheel to run on the rear since the Xtracycle I have is made for 700c and the brake braze-on's won't reach. I replaced the rear der., the bottom bracket, cranks and soon I'll replace the straight bar with a Soma Sparrow bar, which is suppose to be like an English 3spd bar but much narrower.
So essentially, I've been working on two bikes at the same time. Trying to build up my tourer, the Trek, and my cargo bike, the SurlingGary (Surly/Gary Fish mix). The Trek is done. The SurlingGary is a pain in the butt and is still not rideable. I had a shoot today that I had to light so I dusted off my Burley Flatbed . It worked well, but it's definitely not as maneuverable as an Xtracycle.
Yesterday, I took a Road 1 course from Chris Quint, a League of American Bicyclists Instructor. It was great and gave me a bit more confidence in what I was doing. If you have an opportunity to take the class, I highly recommend it.