K & W HO Scale Model Railroad, Construction Update #7 - East helix reaches middle deck

This will be a regularly updated record of the construction process of my model railroad layout. Details are listed below:
Scale: HO
Design: Triple deck, around the walls with a peninsula and two helices
Era: 1980's to Modern Day
Roadnames: Missouri Pacific, Southern Pacific, Denver & Rio Grande Western, Santa Fe, BNSF
Style: Prototypical-Freelance
Size: 26'x15' with a 14'x5' leg
Construction: Combination shelf and box frame
Materials: 1/2" plywood base with varying thicknesses of foam board subroadbed, over 1x and 2x lumber frame
Track: Atlas Code 83 in Staging and helices, Micro Engineering Code 83 on the main lines, Code 70 everywhere else
Minimum Radius: 26"
Minimum turnout frog: #6
Lighting: LED fixtures and strip lights
Operating System: DCC NCE PowerCab with booster(s)