[OrrieG]

Set up your motor so the carb base is parallel with the main frame, that will give you about 4 degrees down at the transmission and keep your carb level. Then start measuring, seems like each application is different. 57 did not have transmission crossmembers, the bellhousing were supported and the trannys hung loose. You might look and see if a mid 70's truck one will work, the did have trans mounts. Or it is easy to fab one out or tubing and flat stock.