Here's a sketch of the roof rack. I was trying to choose between Alurack and Vantech:
Alurack: The crossbars attach to a T-slot on the side rails. Accordingly, they can be moved forward/aft to miss my roof vent and such (Yay!). However... the crossbars don't have slots, so it would be annoying to mount everything (Boooo!).
Vantech: More sturdy because it mounts with 6 gutter mounts instead of 4. The cross bars have slots (horray!), but their fore/aft positions are fixed (Noooooo!). They insert into milled pockets in the side rails, so moving them would require a bit of machining.
In the end, I decided on a bastard cargo rack: Vantech gutter mounts, Alurack side rails, and 8020 crossbars.
Side Rails: The stock Chevy Alurack uses 120" siderails. You can buy just the side rail module (PN PD-AR-2104) for $346.65. However, I'm going to use their 128" rails for $401.15. The extra inches will allow me to fit the longest truck boxes that I could find.
Cross Bars: 8020 is half the cost of factory cross bars. For example, a Vantech H3 (1.5"x3"x65") crossbar is $120.12 while an equivalent 8020 extrusion is only $53.30. I'm using 5 cross-bars, so I'll save around $300.
Flooring and front Catwalk: It seems that folks are really happy with Farmtek chicken coup flooring. A 4ft x 2ft panel is only around $25. Most people attach this with zip ties, but I might attempt a flush and I'll hold down the edges with overlapping L-track.
Truck Boxes: The sketch shows two 62" Weather Guard boxes. These are a little pricey, but still comparable to Thule boxes of the same volume. I'd certainly feel more secure about leaving my climbing gear in the Weather Guard. They're also sturdy enough to sit on, so why not grab some marine cushions and a removable pedistal table? I'm still concerned about my gas mileage and I may try to find a lower box.
Solar: I'm going to reuse my existing 100W Renogy panels. However, I'm going to mount them subflush to the crossbars. That way, the cross bars are still available to support lumber and surf boards!
Girl: The girlfriend is a possible future addition, but probably outside of my current budget
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