Yes- - - -the bell housing bolt pattern, input shaft, and clutch should be the same for both transmissions. There are two different lengths for the output shaft and rear housing, so the length of the driveshaft and the position of the rear crossmember would vary according to the application. The SM 319 is a 318 with the Borg-Warner overdrive attached. The output shaft and the main case are slightly different, but the majority of the transmission internal parts will interchange.
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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