1) You should be able to pull the 42t and 22t chain rings off your crank set. Voila... a SS crank set.
2) Why go EBB? Is one even compatible with your existing threaded BB shell? I'm not an expert, but the retrofit EBBs I've seen are for press fit BB shells. Doesn't your Durango have a threaded ES25 BB? I would (and have) replace the rear derailleur with a chain tensioner.
3) A SS cog conversion kit should have the cog and spacers of various widths that will allow you to line the cog up with the front chain ring on the freehub (after removing the cassette).
4) You can just re-use your existing chain.
5) Yep, all easily removed.

On a side note, have you tried choosing and sticking to one single gearing combo with your existing setup to see what size cog you'd want and whether or not you want to go the SS route?

Here's my SS conversion with drop bars (basically following my own advice for the conversion, except for the chain):

Untitled by tk_1971, on Flickr

Another picture of it in full Ti mode. 19 lbs and change here:

Untitled by tk_1971, on Flickr