get everything hooked up, and jack the front wheels off the ground. with the engine OFF fill the fluid, and s-l-o-w-l-y turn the wheel lock to lock about 10 times, and recheck the level. top off as necessary. repeat as many times as it takes to get everything full. then, start it up and do essentially the same thing, but don't hold it at full lock for more than a half a second or so. that's hard on the pump. this should get everything all primed up and most air out. hopefully, you wil lbe lucky and the pump won't be toast.
i had the same deal on my 78 Ford LTDII that i got back from my cousin- he drove it for a year and a half with the PS belt hooked up, but no fluid in it from a cracked high pressure line. threw on a new line, filled it, and it works sweet. i can't explain it either...
oh, make sure to use power steering fluid, and resist to use up that quart of Dexron 2 you have had on the shelf for 3 years. ps fluid is cheap, and you really don't need that much of it.
you don't plan sincerity.
you have to make it up on the spot.
wanna hear about 20 years ago when i was too smart to know any better?