I've been pondering this for a while and working on it for a couple of hours here and there without much progress. I tried a ton of different configurations for this over the last week or so and think I finally have a handle on it. Lot's of guys do these with the filter stacked on top and a bunch of curved tubes going every which way. The rats nest of fuel line was one of the things I was trying to get away from, and after measuring, sketching, trial fitting, etc. I think I finally have a handle on this.

I'm going to flat pack the assembly in basically the back 1/2 of the tunnel and raise the tunnel cover by about 2" This will simplify the plumbing runs, leave lots of access under the selector valve for what's going on there, and give me a place to put cup holders and maybe a fire extinguisher.

Plumbing and trial fit done, although theres still a lot of fab work to make this happen. Lot of work for cup holders!