Near stock 73 Swinger first time at the track

Without getting crazy, the first thing I would do is get a set of M/T ET street drag radials. You never said if it had a sure-grip so if not install one. Up the gears. I not sure what the stock gears are but I bet they are not helping you launch. 3.73 or 3.90 will help you launch and still be good on the street. You could get a bigger stall convertor and shift kit for trans.
I know there are alot of other things you can do as far as motor goes but like I said these are a few things that can be done without getting into a crazy car transformation.
You will improve your 60ft times and lower your E.T. some but after that I figure a mostly stock 73 Duster w/318 will be low 16's.

Let us know how it goes.