...and I didn't want to dump oil all over my still clean motor.
No, it wasn't seized, just wouldn't hold pressure. I guess the piston/bore wears after awhile or the check ball doesn't seal any more...or air gets hopelessly trapped inside. Once full of oil, they should feel very hard. The point is, they fill to take up the exact clearance of each individual valve, removing any need to adjust or measure anything. The 8v lifters are nearly identical to the 16v parts only bigger.