If the Sedan Delivery uses the same bellhousing as the pickup, the swap will probably be pretty simple. The car transmission had a very different bellhousing bolt pattern than the truck 3 or 4 speed. I'm not sure which driveline components the Sedan Delivery used. There might also be a difference in the length of the torque tube and a different universal joint which would need to be adapted to the 4 speed transmission. The swap might not impossible, but it's probably difficult.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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