Wow, this is just too fantastic! It is really getting there!
Admit it; you know you've been thinking about what to do next...
As far as the Tamiya white X-2 peeling; have you tried the Tamiya low tack masking tape? It's expensive, but seemed to work for me, and I also used X-2 on a number of Porsches.
If you're printing the enlarged 1/8th decals, how come you can't use the stripes? I notice your enlarged copy isn't color (mock up?), but surely that would cause a problem for the logos too? Not understanding... If you could successfully print and use those stripes at 1/8, what a headache that would eliminate...
Keep the updates coming!
ianc