On my cars, the leak has usually been from the large but thin seal between the bottom plate and the housing where the steering shaft comes out. To remove the bottom plate, you take the pittman arm off, and remove the screws. Have a pan handy to catch the fluid. The seal is probably dried out. It is difficult to remove, but with a dental pick and some patience you can remove it. Press the new seal in and reassemble.
To get a new seal, you will need to buy an overhaul kit. I get mine from Authentic Classics.
Misc tips. Mark the pittman arm and shaft before you remove it. Get a M8x1.0 bolt (hard to find) and grind or file the end to a point. Remove the top bolt from the steering box, center the steering, and put the new bolt in, to engage the steering shaft to hold it in the centered position. Don’t forget to remove it before driving the car (LOL).
Good luck,
CT
Steering play can be caused by worn bushings in the coupler between the steering box and the steering shaft. To remove and replace the coupler, undo the five bolts at the inside firewall that hold shaft’s cover. Pull the cover up to expose the hex bit screws. Remove the screws and slide the coupler down and off. Replace the bushings and re-install. Be sure to have both the wheels and the steering wheel centered. An unpleasant job.