Engine Balanced

I am considering doing a four speed conversion on my 71 Scamp which now has a 904. It's got a 360 in it and I am being asked by Passon "Is the 360 neutral balanced or is it still 360 balance?" How can I tell? I had the engine rebuilt a year ago and they machined the crank and reused the harmonic balancer and I believe the engine is a 74.