Was wondering about gear ratio's which I don't know Jack about, it was said to make sure my differential would be a good match. I have no idea what a stock 47 had.
Most '47 era cars came with a 4.11 rear end - though there was a 3.73 option. There are no external markings on a pumpkin to indicate installed ratios (like the later metal discs).
Direct inspection is the best approach. 4.11 pinion's are marked with gear count 9-37; 3.73's gear count 11-41. In '50 the Power Glide was introduced with a 3.55 - gear count 11-39. All are marked with month & year of manufacture.
