I have a '52 M38 A1 with an 11" drum Dana 30 swapped in, and that is great for that app. But my experience with the exact same brake on a 1000+ pound truck is they need an upgrade...
I THINK the Legend wheels have a big enough pilot to fit the early trucks, but any wheel that fits a 6 lug 4x4 solid axle Chevy will work.
Here's mine so you can judge. Front tires 27" tall and rear 29"
EDIT: But the 5 spoke wheels fit perfect with the ECE conversion disc kit! 2 1/2" spindle and 2" spring in the front with DJM rear flip for 7" drop.