lifter clatter

I have a 360 that I put together 4 yrs ago. I have been fighting a lift tic ever since. Its got a comp cams hydrolic with the specs from a 68 340 4spd cam, nothing wild. When I start it cold it clatters like a bit@$ for a couple seconds then smooth a silk. However, when I drive it and it warms up, I get lifter clatter not bad but there just the same. Called Comp and they told me they got a bad batch of lifters and to replace them. They sent a new set, broke them in and same thing. So now I am getting ready for the summer so I pull the covers off. With the lifters on the bottom of the the lobe, I can roll the push rods with 2 fingers easy. This seems like a little to much, like not enough pre load. Is it possible that I need longer push rods, or do I have another bad set of lifters. This is the first small block that I bilt,sooo now what?