Where to get a 904 flexplate

Here,s one I found just googleing 904 flexplate http://www.csr-performance.com/shop/category.da/flexplates/chrysler-flexplates

I found lots for the 904 on Mancini,s Racing site,check them out.They have about 5 different ones.Good luck

non of the flexplates refered to fit a slant six crank. It is possible, by calling the vendors, you might be able to get one special drilled for the slant six crank pattern.