When I rebuilt my 292 a couple of years ago it had a flywheel that had holes all around the outer perimeter. I had never seen one like this before and couldn't identify it and thought maybe it was some old method of making it lighter?  Then I saw this listing on Ebay the other day that looks exactly like it and says for marine use only?    Now I'm really confused LOL
http://www.ebay.com/itm/FORD-Y-BLOCK-292-INTERCEPTOR-MARINE-BOAT-ENGINE-MOTOR-FLYWHEEL-FLY-WHEEL-/141509066402?hash=item20f298fea2:m:mRs-wp98k4_GwTyM2n1opeg&vxp=mtr