What to expect out of mild build 360

Agree completely
I would add( and i bet you agree) thinking what something will run, and actually getting to the track and putting down the number are way more often than not two completely different things.
The OP has some good parts, no doubt. But getting to the track can be extremely sobering..... lol..... just the tire he has on the car could make a 1/2 sec difference in ET..... one way or another
100% agree! A lot of "12 second" street cars go down to make a 14 second pass... LOL. And it isn't always traction, sometimes they have a 12 second car because somebody "told" them it should be 12's... LOL