I've had something like this on my mind for a while as well. I'm not big on A-pillar pods (not very stealthy), & things placed in front of where the gauge cluster is would be IMO obtrussive.
my mother has a 96 Montero SR (full size), & the location of the three gauge pods is good(but not the boxy akward pods themselves). just like when I had my 3000GT, I really liked the three OEM pods in the middle of the dash. best thing about these were that they angled towards, & slightly sweapt around the driver. there was even a company (Blitz I think) that made an extra two pods to add on to the other three while maintaining the same angle, & sweep.
you know that our dashes have an akward step. from the windshield it takes a step down where the clock face is. it comes out again, & takes another step where it meets the center air vents. from the middle, outwards, to the left it slopes up to meet the level of the gauge cluster trim, & to the right it slopes down toward the passenger side dash vent.
well, the point I'm getting at is that if you can imagine there being no 1st step (for like where the clock is), & making something to fill the void that maintains the initial slope from the gauge cluster trim. since this would be a prototype, make it our of anything thats moldable, sandable, & pliable. (wood, plastics, some metals), one great thing is Epoxy Putty, it molds like clay, sets like steel. could be sanded, drilled, cut. they sell it in the plumbing section at home depot for like $6.
this "something" (oval like board looking trim) can then be cut & angled for whatever you want. out of this oval board platform you can make additional angled trim pieces (possibly molded from A-pillar pods) that go around boost, EGT, Gauges & the SAFC too. these trim pieces can be glued by you, or the buyer with special stuff sold here:
http://www.crestnetsales.com/plasticrepair.htm
best thing, I think this design has is its user friendlyness. if it were possible to make the board to snap on & off easy. it would make it that much more easier to access the gauges (or what have you) & mess with them from behind. it would also mean that the face of the motherboard would look more clean flush. not to mention the hole left by the removed clock would be an easy access way to run any wires, vacume, or probes lines.
for some people that say it is not a good idea to put any of these instruments in the center because it is akward & impractical to see while driving. to some extent, I agree. theres plenty of things I mess with & glance at while driving thats located in the center. (i.e. rear view mirror, vents, climate controls, Radio) the only time I'd say that all eyes should be on the road, (with minor split second glances at your main cluster) using your perripherial mostly would be during a race where you're gonna be agressively driving, & more than likely not be monitoring all your gauges & messing with your AFC. IMHO you'll monitor these devices most during test & tuning, & its then when you can best put the info provided to imrove your cars performance.
just my $0.02