push rod ?

IIRC,Those lifters will all have oiling holes in them. So what goes where? IDK
The intake rockers work a little harder. The valve lift is usually a little higher and therefor the spring pressure over the nose will be a bit higher,and the valve is bigger/heavier.Some might say to put the hollow ones on the intakes.
Some might say to put them on the exhausts to provide oil-cooling to the springs. Good arguement.
Unless someone replies to the contrary, I would put the hollow ones on the exhausts.