The overall diameter of a 700-17 tire is 31.6" according to Coker.
Checking on Tire Rack, the only 235/85R17 tire available there is a temporary spare, which you don't want to use. But LT235/80R17's are available with a diameter of 31.8". They're Load range E tires, which might ride a bit rough on a '41 truck.
The other thing you might take a look at is the width of your rims. The LT235/80R17's usually mount on 6.5" wide rims.


Kevin
1951 Chevy 3100 work truck
Follow this saga in Project Journal
Photos
1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.