Newbie Restoration 1956 G11

[Tenshi]

Hi to everyone. Am new member from Awestralia and in much need of much help! I have a basket case G11 and have as many questions as I have parts to assemble... so here's the first one. How do I tell what year model the crank comes from? Why I'm asking is because the centre web plate is way too wide to fit into the crank The #'s cast into the web plate are 013776 and the only markings on the crank are m18 stamped into webs and F on the L/H side and A on the R/H side near the mains.