It was rather common to buy a vehicle in the 1950's and then try to haul more with it than it was designed for. There were adapters sold in the 1950s and 60s to make dual wheels out of singles. They used the regular wheels that were designed for singles and you had to remove the outside wheel to check the air on the inside tire. Quite often they removed the fender all together or made one out of an old barrel. On a flatbed it didn't make any difference. I run singles on my bulk hauling fleet. 445/50R22.5 on aluminum hub piloted. It would take quite a bit of horse power just to turn them. As for the cost, $1,200 is list. I buy them for considerably less on my Michelin national account.
https://photos.app.goo.gl/2Nc2RCZ4gKu1niXH6
