Problem replacing American Standard shower diverter stem.

I got the seat out

I did indeed get the seat out, using the standard cheap seat tool and smacking it a bit with a hammer to get it to bite into the seat (which created enough purchase to torque out the seat). Put in a new seat, new diverter (stem and barrel). Alas, still drips from spout. The diverter was just metal against the seat; there must be a washer or Irving missing.

Hey, did you ever figure this out? I am having a similar problem. I have worked on these Am Std heritage faucets for years but alweays the valves. This is the first shower diverter that has given me a problem. I replaced and greased the whole assembly,(seat and washer) and if I remove the shower head i can get 85% flow up top but when i add the shower head the added resistance pushs half to the spout. I am wondering if it is an alignment issue of the barrel holes in the valve body????