Low money 360 any ideas

So just got a 74 swinger with org 318 (alum. intake elb. 4bbl) 727, and 7 1/4 rear. so i have most of my extra cash tied up in full floor pans, interior, and fixing the paint on top of the car. But manged to pick a running 72 2bbl 360 with 55k on it ($200). any ideas where to spend $500 to get the most power i can. I already have plans for a dana 60 out of different budget