From an old post:

“I have Cooper Tire SRM II LT215/85R16 black truck radials on my Suburban (they are pretty old, 10+ years).

The 1954 16" rims are 4.5" x 16".

Your 1947/48 rims might be either 4.0" or 4.5"

The mounted tire diameter, as Carl posted, is around 31". The "advertised" diameter is around 28".”

3.55 ring & pinion and all new rear-end and torque-tube and u-joint parts.

On a long flat straight empty road, I once had in up to 93 MPH - to impress a friend.
He was not impressed until I told him to check the speedometer.

Never again.