I am in no way connected with this offering or the others by this seller.
Here is a link to one, check out the seller's other items. Looks like what COBRA lettering got added to for 'safety' bell housings for five bolt engines.
https://www.ebay.com/itm/An-Authentic-1963-Print-Of-A-Shelby-American-Clutch-Flywheel-Housing-Blueprint/163680645159?hash=item261c207027:g:cKwAAOSw619cuhuO:sc:USPSFirstClass!59718!US!-1 (https://www.ebay.com/itm/An-Authentic-1963-Print-Of-A-Shelby-American-Clutch-Flywheel-Housing-Blueprint/163680645159?hash=item261c207027:g:cKwAAOSw619cuhuO:sc:USPSFirstClass!59718!US!-1)
John has a LOT of stuff. I went out there last June to visit my old car an got the tour of my life. 8)