Valve adjustment question

[lukecp]

I just got done adjusting the valves after putting new heads on my 350. I adjusted the valves as instructed by my Haynes manual. I put the #1 piston at TDC on the compression stroke, then tightned each rocker nut until i felt a drag on the pushrod while turning, and i could no longer move the pushrod up and down. I then tightned each nut another 1/2 turn. I adjusted all of the valves by turning the crankshaft 90 degrees, and in the order of the firing order. After i adjusted them, i went back over them to double-check everything. It seems that about half of the rockers have a bit of play in them. That means i can grab the rocker by my hand, and it will move a little bit. Is this normal? I thought they were supposed to be movement free?

All i need to do is put my carb, headers, valve covers, and vaccum hoses on and start the truck up, but i want to make sure i didn't screw up the valve adjustment.