1978 Oldsmobile Omega

So I got the heads back on my 350 that I tore down to re-gasket and paint just for a driver motor while I build one, I cleaned my pushrods and blew them out with compressed air, I have noticed that one side of every pushrods is slightly smaller in the oil passage, should the smaller end go upward or down or does it matter? I assumed it was to restrict but I didn't know they did on stock pushrods?
Any help would be great, thanks guys