Dany's race car adventure, or help us spend my last $1500 wisely!!

So Dany and I will be headed to Edgewater on Fri/Sat so she can have a try at brackets there this week.
She was the SLOWEST car at Thornhill last time and probably will be at Edgewater too, and i know brackets is about consistency but it would be nice not to be on the "bottom".
So, here is what we have:
'66 Barracuda weighing in at 3400 lbs with a half a tank of gas, the spare and jack, and Dany in the seat
904 auto (18 spline)
3.55 Sure Grip
Line Lock
Stock 273 2bbl (in car now)
'01 Magnum 5.9 take out with exhaust manifolds
Crosswinds intake
stock harmonic bal with bolt on pulley
LA timing cover

What we need: (NOT in order of priority)
Full gasket set for the Magnum
360 car pan and pickup
valve springs
camshaft
timing set/tensioner
carburetor
convertor
water pump and bolts
thermostat housing
air cleaner
and last but not least..
HEADERS!!! (and pray the heads aren't cracked!!)

So assuming I DON'T need heads, I know I can go thru the motor, slide the cam/springs in, set it up as an LA and stick it in the car for less than $1500...BUT...
Early A headers (Doug's or TTI'S are the only choices if I don't want to cut the fenderwells)
are like $1000!!!
Not saying I won't buy them, just can't do it now with everything else.

So, do I forgo the cam, springs converter and put the headers on the stock motor?
This is why i mentioned the slant converter in the other thread, its 18 spline, raises my stall some and is a bolt in. and should be a cheap one on this site somewhere!!

Or, do we cam/spring the motor and add headers later when i can scrape up the money?
I have a Ben Pearson exhaust bender from my "previous" life so i may be able to get the right Magnum manifold to work. The car will need some kind of exhaust system(headpipes,mufflers,downturns? car is driven 40 min up the interstate to the track) the left 273 manifold will choke the **** out of the left side!!
Any advantage to port matching a 318 left manifold??
340 manifolds are half the cost of the headers, so I don't see that as a practical temporary fix.

I have gotten so much valuable advice on this site, as there is so much experience here I know some of you have been where I am. We will do all of it eventually, but i am torn on whether to let everything sit until we can do it all, or do it in "stages".
Might be better for Dany's learning curve if the speed came up gradually?

Thanks so much in advance guys!!