Lee, engine modifications for 1951 where weight increase of the crankshaft with 20%, barrel and head increase finning depth, different rocker box covers (round type). So all in all your heavier crankshaft is correct if it's a 1951 engine!
Today I did received the KH pistons from the club. Weight seems the same as the originals. They look fine Top ring chrome, middle normal, oil control rings are in a different configuration as you can see on the photograph. Thanks, Colin!
Yes, that's looking great! Unfortunately money is drying up, so for me out of reach. Hope I can finish my project within reasonable time and not will loose interest... Knowing myself I'am not a very patient person when it comes to projects!