I know from the painting operations here at work.. you loose roughtly about 1 psi for every 10ft of air hose.

This anywhere close to true when dealing with the smaller ID vacuume hoses we have on our cars? I know im not dealing with 100-120psi here though too

I dont see how it will be that much of an issue if I was to do this, expecaly with my megasquirt set up correctly in case of overboost

Boost guage will show 10psi weather or not its set that way from in the engine bay or in the dash I would think

Any other thoughts?

how this would be routed maybe?

 

It's probably OK just use real small ID line. I don't see the appeal to running the MBC to the cockpit though because boost gauges are not very accurate - easily plus or minus 1 or 2 psi in many cases, so it's better to verify through the ECU MAP sensor what pressure you are at - which you can't do on the fly if you want to be turning the **** on the fly.. and most MBC's you tighten down with a wrench once you have set it to where you want it anyways, so you'll need to bust out the wrench to change the psi whether it's in the cockpit or in the engine bay...