I find that the best option is using a floor jack and lifting the car from the suspension. The bumpers on the 51 to 55 cars
really aren't that heavy and using a jack of this type or a bumper jack may well result in bending the bumpers. The early series cars, with the exception of the really heavy ribbed bumpers used on the Frazers suffer from the same issues. If you
have nice chrome on your car or if you have re-chromed bumpers - I'd shy away from using this jack.
I have one at my shop that has been sitting on the sidelines for years - and aside from trucks with heavy step bumpers on them - I simply just don't take a chance using it.