408 vs 600 stroker

I want to obtain majority of the parts before I purchase because if I buy the car now its going to just sit any way, at least this way I have garage space. I was also leaning towards a 408 because I have a extra 360 in my garage... But I found some one who wanted to trade for a 440 so either way I am ok.

My plan is find the motor I want. Get what ever block I choose tested and cleaned. Acquire the engine parts, drive line and rear end (already have tranny), then buy car. Get it blasted and painted