906 Magnesium Upper Valve Cover / Casting Part Number: 901.105.115.10 ~ 901-105-115-10 ~ 901 105 115 10 ~ 90110511510 See here https://pbase.com/9146gt/image/156947767

906 Magnesium Lower Valve Cover / Casting Part Number: 901.105.116.11 ~ 901-105-116-11 ~ 901 105 116 11 ~ 90110511611 See here https://pbase.com/9146gt/image/156939935

Here is a "Want to Buy" thread at the Early911S I started http://www.early911sregistry.org/forums/showthread.php?103207-WTB-906-Magnesium-Valve-Covers-Upper-pn-901-105-115-10-Lower-pn-901-105-116-11&p=751422#post751422

FOR COMPARISON PURPOSES ONLY! I included some photographs of the more common early 911 (65-67) Aluminum ribbed valve covers https://pbase.com/9146gt/image/156939907 NOT the same as the 906 (of course in Magnesium), but they all have something in common, they leak like a sieve when not properly installed. LOL