If you want visibility of the gauge probably the steering column mount is the best. You can choose to mount either one or two.
http://www.europeanautosource.com/pr...f3f8c488c486f1
There is also the option of a pillar mount. I think the original P3 gauge was a small mount near the bottom of the pillar. This would have excellent visibility, but probably impossible to find now.
I've seen someone on here that cut one of the slots below radio/climate and mounted a gauge in there. From what I remember it was clean. This is assuming you don't have heated seats or any buttons on the panel. IMO, this is much farther distance from your normal driving view, so it is even farther out view than the P3 Vent. This seems like it would be much harder to monitor while driving WOT or anything more than a glance really. Also, it is much less likely to look OEM, because if you are cutting and putting in pieces of plastic and such, it is not going to look factory. FWIW, the P3 vent is a bit out of view and you have to look down with your eyes to see it, but I have no problem monitoring it as I drive. The V2 also has a record function, so you can watch the last 15 seconds of driving for whatever parameter you want. People always ask if this is a factory gauge or BMW OEM, so it looks very clean. Seems like you are really against it though, so you're probably going to have to build something yourself as opposed to a PnP solution.
At least one improvement may be to talk to Leatherz to buy the gauge, because he has a cover for the gauges to match the interior light to the BMW, so it should match better.
Tim