i think the goal of a high 9 second car anywhere underneath a $15,000 budget is pure pipe dreaming, especially if you want to keep it running. but here's my opinion..

a very well planned/built/balanced 500+ cid built solid roller BBC
VERY worked heads, probably going to have to use some AFRs or something like them, then pay to have them worked over
tube framed 2nd gen camaro
fuel cell
ford 9" with spool and probably A LOT of gear
90/10s
transbraked and built th-400
a lot of lexan
a lot of sheetmetal
a lot of tire
a lot of suspension work
a lot of nitrous
a very expensive fuel system
a very expensive oil system