I just installed my pod+gauges this weekend. And to the people who always say search.. most of the previous threads suck and are worthless (probably why people keep asking

).
I pulled up all the sound deadening from the drivers side firewall area and moved the fusebox out of the way so I could get a better view of the potential areas to drill holes. I needed enough room for my 3 mechanical gauges... 2x7/8" and 1x3/8" holes. In the engine bay, if you remove the cruise control module, you can see the big flat area, but only the top portion (but below the wiper cowl) is "open", as the fuse box is on the other side. My 3 holes were next to each other (allowing room for their 3 separate grommets) inbetween the big wire harness and the fuse box mounting stud. From the inside... the tubes are above the fusebox and don't touch anything.
All in all... I wasted so much time reading "related" posts and trying to figure out where they were talking about. The other areas mentioned *might* work for electric gauges though (existing 1/2" hole next to the hood release cable grommet)... but even then, where I drilled was extremely easy and not in the way of anything. I'll try to snap some pictures and post them.
Oh.... 2 of my gauges were oil pressure/temp and I needed to run them to my relocated oil filter adaptor. I cut 2 more holes in the foglight/horn harness grommet under the fusebox. Enough room to not kink the copper (temp) and plastic (pres) tubes. All nice and tidy