Yes, your '47 wheel will fit the '40 drum, but as has been said, the
lug studs on the '40 drum will be to short for a safe fit of the '47
wheel.
The '40 and the '47 wheels have different styled lug nut holes !!!
Click on pics to Enlarge
!st pic is '40-'41 Ford Wheel... 2nd. pic is '46-'48 Ford wheel.
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If mama ain't happy, ain't nobody happy.
But if daddy ain't happy...
RUN
What I GOT DONE TODAY...
I put my rear-end in the recliner, and
now I'm going to rest up & watch TV.