It's been a while since my last update.
The "Big Trak" platform has been discarded in favor of a full size mild steel & fiberglass prototype. EMI problems and weight limitations ultimately did it in, but what I learned from it was helpful in refining the final design.
The new chassis (still incomplete and in the welding jig) is all that's pictured right now. But the electronics were significantly improved over what was previously listed on my page. I hope to have the chassis welded, ground, painted and crawling tentatively around the living room sometime this weekend.
Updates, pictures & diagrams will be sporadic. Added as cash, time and motivation allow.