'57 Pontiacs use a 5" bolt circle. They use 1/2" right hand studs on the right side, and 1/2" left hand studs on the left side, they will be marked with an "L" on the end of the stud.
If you want to know what wheel size you should have on your '57 Chevy you should go check out this website: www.trifive.com. They got many threads with good answers on your questions about cars.
FORD
There are direct bolt in replacement wiper motors that are electric for that 57. Go to "Hemmings Motor News" and you will find companies that will have those available.
Wheel of Fortune - 1983 16-57 was released on: USA: 24 November 1998
Wheel of Fortune - 1983 11-57 was released on: USA: 23 November 1993
Wheel of Fortune - 1983 12-57 was released on: USA: 22 November 1994
Wheel of Fortune - 1983 18-57 was released on: USA: 21 November 2000
18463572...
Try e-gunparts.com I have an extra Winchester model 69a/75 and i guess it fits the 57 bolt just contact me if your interested in purchasing or trading
I have new replacement magazines for the Winchester Model 57. sales@countrygunsmith.net
about 75$