There was a power steering option for TF trucks. Like the car it was an assist which supplemented the stock steering box and also used the generator mounted steering pump. They were rare and likely not many around now. They didn't work well if the gear box and related components were worn. There was an aftermarket unit on the market for a while that used a similar control valve and ram.
I installed one on my 56 but it didn't give a good feel on the road. I ultimately replaced it with the Toyota conversion which is likely what Ed is referring to. There is a lot of information on this site about PS conversions.
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