Do I have to re-balance this 360

I know I'm gonna have to break down and find a shop to do it but I was just hoping to get away with it like the good old days when we would swap them old TRW forged pistons into a 340 and crank it up and go. I guess back then we didnt know any better or were just too broke to care, I remember doing all kinds of crap back then that I know better than to do now, and getting away with most of it!