If I bought one of these NOS engines I would tear it down and check for damage do to setting in storage for 49 years and to relube all bearings and cam surfaces before I ever tried to turn it over. Also to make sure rings hadn't stuck in piston grooves. I would think that gaskets and seals might be affected by 49 years of storage.
Just my thoughts.

Been there, Done that, Hope to live long enough to do it again.
Big Bill
I.I.# 4698