The reason your car is leaning to one side is most likely not because there are no shock absorbers. A Model "A" can sit perfectly level with or without shocks. Most Model "A's" lean to one side or the other because whoever installed the front and/or rear springs did not get the center spring bolt head to seat properly in the respective crossmember, OR the hanger nuts were tightened without first leveling the frame. I've heard the argument that overweight drivers have caused the frame and body to lean to the left, but I think Haystack Calhoun would have to be the driver and have abused the car over many decades for THAT to explain such a lean.
To correct your lean, simply loosen the front and rear spring hanger nuts. Then stand on the runningboard on the high side and use your weight to flex your knees up and down to rock the chassis. This will "slide" the frame in the direction you are standing and change the lean. Get off the running board and check the levelness front an rear. Don't trust a measuring stick at the bumpers because the brackets may be bent or other factors may give a false reading. Use your eye to tell you when levelness has been achieved. You may have to go back and forth from runningboard to runningboard before the car sits level. When satisfied that the car now sits level, be sure to check that the center bolt head in each spring has nestled into the crossmember hole. Tighten up the spring hanger nuts evenly so that you don't pull the frame in one direction or the other. Test drive the car to ensure the new setting remains. If so, replace the cotter pins.
By the way, some guys like to put a VERY SLIGHT lean to the passenger's side so that when they are in the driver's seat, the car will be level. If your springs and hangers are in good shape and you're not Haystack Calhoun's twin brother, this shouldn't be necessary. Go for a level stance with the car empty.
This suggestion does not imply that your car doesn't need shocks! It does need them if you want to achieve the ride and handling that were designed into these cars. The foregoing is only intended to get the car level PRIOR to installing shock absorbers.
Marshall
