You've got the late-model Powerglide with the aluminum case, which, other than being short one gear, is a pretty good transmission. They have been highly modified for drag race and circle track use and worked very well in both applications.

It's not the ideal truck transmission, but for a weekend cruiser or a daily driver, I think it would be wise to leave it "as is".
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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