Very nice work SmolderZ. But aren't you affraid there is insufficiant clearance between your doublestack car and your snowshed's roof? What happens if ever your track work bends or gets tilted with a change in heat or humidity?
Myself I'm very far of beeing at this stage as I'm just beginning to lay my track, but when it's time to scratchbuild my tunnel portals (unless I find them commercially available as I want to have models of those existing on the prototype Tehachapi Pass), I will adopt a higher clearance, in order to accomodate the slight changes of scale among various manufacturers (for example, if you couple a Micro-Trains Line Gunderson double stack with a sample from Harald Freudenreich, you see that there is a one or two-milimeter difference in height...).
Dominique