UPDATE TIME!
Ok, 6 months isn't exactly soon, but the roof is sky high and I'm happy and what else really matters?
About 3 weeks ago I finally chopped and raised my roof 18". Since then I've been inundated by rain. Shoulda built an arc, not a bus. This took a lot of research, planning, and material sourcing. Who knew 1 3/8" steel square tube was so hard to find?? I had to pay $5/ft (incl freight) to get mine. I actually believe this will be stronger than the "hat channel method", which is important for me because I still want a roof deck.
Method: Remove windows, rear doors, and rear exterior panels. Liberate front cap. Weld on 4x threaded supports. Drill OEM hat channel for plug welds, and then cut hat channel. Pray. Lift front - back - front - back ..etc about 4" at a time with a floor jack and a 4x4 timber until desired height is reached. Use big f'in hammer and c-clamps to coerce 1 3/8" square tube into its new home in hat channel. Weld.
Bonus: time lapse!
Next up: window framing