As you indicated that the truck has the 7 bolt side cover trans it should be very similar to the Chevelle trans as it would be from that era.
The mounting and input shaft is the same from 48 up on trucks and 55 up on cars. The differences could be the shift arms and possibly the front driveshaft yoke.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine