Now I'm puzzled - The Chev CMP manual also lists 590383 as a spring - "Spring , Gearshift Lever" - located near the base of the lever. I believe 590383 is the spring shown as #69 on your diagram.
590388 is one of the part numbers common to both Ford and Chev CMPs but on the Fords it is only listed for 30cwt and above. The Ford number for the spring is given as C01Q-7966.
The barn Bob refers to is his "Hammond Barn"
http://www.mapleleafup.net/forums/sh...ad.php?t=17780 that he is kind enough to share with Rob and myself.