From the two 292 Chevy IIs I have had, 12s even at sea level in an easy to drive car, will be very difficult without forced induction or nitrous.
My 66 2dr all steel sedan with full interior, stereo, pump gas 292 with solids, 4 speed and 4:10s ran low 14's at close to sea level. My all steel 63 with gutted interior, strictly race 292, glide and 4:56s ran mid-12s at the same track. The car without driver weighs 3100 lbs including a 6pt bar and subframe connectors.
To do what you want to do without some sort of adder, you will probably want a lot of gear and an overdrive trans to make it liveable on the street, a lot of fiberglass body panels, maybe lexan side and back windows etc. For 99% street car, I would shoot for 13's and have a very nice driver.
