I should be able to help (I just finished building mine
)
First, there is a big difference between 6-8 and 12-15 psi (Assuming you're going to run an 18g or comparable sized turbo). For both setups I'd recommend:
Pistons (about 9:1 CR)
A good intercooler
larger injectors (350 or so for 6-8psi, 500cc for 12-15)
A 3" exhaust system (Thermal R&D makes an AWESOME system)
adjustable fpr
fuel pump (190lph should be fine)
Apex'i AFC
some kind of boost controller (manual = cheap, electronic = sweet)
ARP head studs
Gauges: Temp and Boost
For 12-15 psi, I'd start looking at the following:
Rods
Hondata (but AFC would probably be OK)
blockguard or sleeves (MAJOR controversy over the blockguard)
Gauges: Oil and Fuel pressure, EGT
Now I like to build reliably, so if some of this this seems like overkill, it probably is, but it costs a lot less to spend a lot money now than spend a shitload in repairs and rebuilds. When you're done, get it tuned professionally.
A tip: however much you think you'll spend on this, add about 50%. Seriously. Good luck.
Also: Don't bother with an A/F gauge. They're useless.