In the midst of the excitement to post your question you forgot to tell us what engine you are working on! In my limited experience with Chevy engines from 1937-1958 the flywheel can only go on one way as the orientation dowels are off set, not symmetrical. Some one with more knowledge than I will chime in soon, but I think you will be all right.

Kent


1937 Chevy 1/2 ton
1942 Chevy 1/2 ton
1947 Diamond T Model 509
1951 Chevy 1/2 ton
1950 Chevy COE Model 5700 ~ "Barney" ~ And more pix