Origin of 1966 GT350 and K-code rear housing center section

[6s1640]

At the risk of revealing another secret, does anyone know the origin of the center section of the 66 GT350 or K-code center section housing.  Is it a Ford Galaxie, Ford truck, big block or?  It can't be unique.  Or the "make from" part.

Thanks

Cory

[Greg]

I believe a big block Fairlane and Galaxie are the same.

[gt350hr]

  Cory,
    The new back cover plate was a direct result of race testing. Because the ring gear "grabs " so much gear lube with the gear teeth and slings it forward , Ford engineers felt that flattening the pass side of the cover would improve the transfer of oil to the pinion bearings.  The "flat" side also allowed a better sealing "plug" with a sealing washer to be used. The new cover was used on all product lines from '66 on until the 9" was discontinued in the late '70s. The plug was dropped in later years because of the plug in the side of the gear case. It was not K code specific , it was 9" specific. While I was "in training" to learn differential service methods ( read rebuild)  a page in the Ford training book mentioned the change and reason.
    Randy

[GT350Lad]

Thanks for the insight Randy, cheers