Last night, I was looking for just a bit of primer to use on a 1/72 P-51B I'm building for a friend and picked up one of the old pactra bottles of "Flat Rebel Gray No M12". It looked like 75% solid and 25% thinner. Never been opened. It took an oil filter wrench and a pair of pliers to get it open. Stuck a toothpick in to see if it was hard as a rock. To my surprise, the toothpick went clear to the bottom. Put the old battery powered mixer in and stirred away. It mixed right up, went on nice and smooth with my Iwata, and this morning it was dry and looks great.
Hope the rest of those old paints I have turn out that well. They don't make them like that any more.
Jim