Since you don't have the truck yet you really don't know what transmission you have, what column, or what shift linkage configuration the previous owner hacked together. Anything you get other than the stock original parts is going to need some sort of modification to make it work. I would suggest looking it over to determine if what you have can be used. Possibly get the factory manual to see what the stock configuration looks like.
Also see if you can find a similar year truck to look at. It could be that bending or repositioning the rods and levers can make it operational. If all else fails there are aftermarket floor shift kits available.
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