OK, this sounds stupid, but I assumed since the stock head gasket has a
"THIS SIDE UP" stamped on it the Impala gasket would . . . wrong.

Which side goes up?

 

Compare the stock and impy gaskets, they should look the same. Specifically look at the metal seals that go around each cylinder hole that are part of the gasket. The seals should look different on the "up" side than they do on the "down" side. You can use this a reference on the impy gaskets as to which side is up, when comparing to the stock gasket.

 

The gaskets are actually quite different. The stockers only have the metal
fire ring around each piston hole. The Impys have this plus a lot more metal
on one side. The PN is stamped on the metal side.

 

Odd, this is the way that the stock fire rings were on my LT1. The fire rings on one side were actually touching one another. They were the same way on the Felpro's I replaced them with (the Felpro's were marked). I just don't remember which way is up. Maybe you can find a pic somewhere of the Felpro's and get your answer. I checked summit, buuuut the pic doesn't have enough resolution to tell anything.

 

I would also like to know for sure, although I read one time that the p/n goes up.

 

I just talked to Karl Ellwein and it seems like there is no real answer, kind
of like it's a trick question. Anyway, he always installs them with the PNs
facing up. This works for me. Just thought I'd post this in case someone
ever searches this up again. And thank you Karl for the info!

 

And 5 years later, here I am searching the same thing.. haha...