replacing power steering pump..

[challngd73]

Ok, my car is a 73 Challenger with a 1972 440 motor.  The power steering pump no longer has a cap, and the pulley is very wobbly.  I tried a saginaw cap, and the federal cap, and neither fit...but I think I need to replace it as it is leaking badly.  How do I know what pump to get, or does it even matter?  Will either one bolt up ok?    thanks in advance.

[the_engineers]

Is the body of the pump round or oval-ish (like a ham can)?  Round is Saginaw and oval is Federal.

[challngd73]

I will have to look in the morning, but i think it is round....the neck is longer than others ive seen though.

[Topcat]

Does it look like this?

[Topcat]

Or like this

http://www.bouchillonperformance.com/BPEPowerSteering.asp

[challngd73]

it looks like neither, im telling ya, the neck on this thing is like 7-8" long.