Fmax vs. local fab: Am I nuts?

[PCT Hiker]

OK, need some quick advice here...

I have a '91 SE-R with a Bluebird DET I installed.  I used the US intake w/
capped egr, the stock t25 and manifold, stock downpipe, AD22VF brakes, a
JWT clutch, and JWT ecu.  The car has stock cat and a 3" crush-bent
cat-back exhaust with a trust muffler.  I fabricated my own intake
(MAF->compressor) with plastic ABS piping, and left the stock topmount IC
in place.  At the time, I also bought the F-Max frontmount spearco IC, the
HKS BOV, and the intake pipe that goes to the TB--all of which are part of
their stage I kit for the US engine.

Today the car is sitting at a local fab shop waiting for IC piping, battery
relocation, and a new downpipe which will incorporate a custom EGR fitting
after the turbo.  After giving some lower figures, the guy now estimates
$3G or more for the complete work order.  Ouch.

Then I got to thinking I could have the rest of the stage I kit from FMAX
(T3/T04E, manifold w/ egr fitting, intake and IC piping, downpipe, external
WG) for much less than that.  Plus at the end, I'd have a BB manifold and
T25 to sell, and a setup that's got potential for much higher ultimate HP
with a few upgrades.  I know I am limited by my stock MAF, injectors, and
transmission, but I thought the Stage I kit was designed for use with 370cc
and stock MAF.

The choice seems pretty clear, actually, but I am wondering if I'm missing
some hidden snag in trying to apply the FMAX kit to the BB motor.  Am
I?  Will the lag from the T3/T4 at low boost (8psi?) suck compared to the
t25?  Will there be problems with oil and water to the turbo?  Would I need
to have Clark reprogram the ecu?  Have to make a decision pretty quick here
since the car's already at the shop...

thanx,
Adam