Questions about 1/48 Bandai AT-ST

Gents,
I won this fine kit in my club raffle, and am halfway done. I have a few questions at this point:
1. I don't think even with my Tamiya Superfine airbrush that I can get into all the tiny nooks and crannies of the sub-assemblies for priming and painting. Do I need to unassemble some of the subsections and then put back together after paint? Will paint on the locking tabs of the parts cause the fit to be too tight, and not a perfect fit like they are now?? That's gonna be a lot of masking ;-)

2. Is there any generally agreed upon FS# or anything for the exterior? I have Gunze and Mission Models paints, would rather not fiddle with the mix recipe bandai gives.

3. How visible will the cockpit be? I'm building this for a contest and would rather spend the time on weathering than on doing the cockpit if it's not visible. Can a judge get his dental mirror into the openings on the front? 
 
4. What's the deal with the decals? Looks like a nice set by Bandai, but they have no placement guide in the instructions, and I've searched online and YouTube and can't find a single model that uses them. Might set my model apart on the competition table if I can find a reference on where they go.

Thanks in advance and thanks to Bandai for a great kit, I already bought a couple more of their Star Wars line.
Michael Smith