I have a 292 in my 56. Engine could use rebuild. There is a good (supposed to be) 312 Crank and set of 8 Rods on Facebook Market Place. Supposed to have been salvaged from rebuilt Engine with bad Block. CDN $400 for Crank and CDN $240 for set of Rods. What is involved in using these Parts in a 292 Block?  Worth while if rebuilding Engine anyway? Thanks