You always find cool stuff Jason!
From the Vin and 7 being 1967 or 1977 also K being Kansas or Leeds assy, the most common possibility is probably '67 Chevelle?
Any signs of a provision for a ntrl. safety switch?
If stamping indicates '67 too, if M is August the high Vin must be late '67 production not early '68?
What others possibles are there also check Vin ranges as not all started at 100001 plus compare stamping w/ any known similar date examples?
Lastly, I tried Google w/ your casting # and got this 1975 newspaper ad that looks like your trans being sold???
http://www.newspapers.com/newspage/47534908/
<span style="font-style: italic">"...Auto Parts, Accessories J -- 15" chrome slotted reverse wheels to fit Chevy product, also with lugs. S100. <span style="font-weight: bold">336-3610 J speed MUNCIE </span>with Hurst shifter. Zoom clutch AFS, Sun tack - like new. Call 52S-3S40..." </span>
[img]<<GRAEMLIN_URL>>/beers.gif[/img]
~ Pete