Please help I have my truck apart now

I am replacing ball joints on my 97 Blazer 4X4 4Dr.

I have had them replaced once before and since then I have had a humming noise while on the highway. The garage was supposed to do an alignment on the rig at that time.

Current situation; I now have my truck apart in the garage and am replacing the ball joints for the second time since owning the truck this time I am doing it myself.

Can anyone please tell me the following. Does the upper ball joints Drop in from the top of the control arm or bolt in from the bottom of the upper contol arm.

Please help, I want to try to get my truck back together tonight so I can get to work in the morning.

Jason

there might be a diagram in your manual if not i'll look at mine in the morning and tell you

I'm pretty sure they bolt from the bottom (aka A arm on top, castle nut on the bottom). Just like the bottoms if I remember right.