Which valve seals for exhaust side?

[6 Nebraska IDIs]

Alright with the catastrophe I had with my machinist installing the positive seals on the exhaust valves in my brown trucks motor, I need to figure out for sure which seals need to go on those valves.
I had a bag of yellowish white plastic umbrella seals and a bag of white little disk seals along with the positive seals in my gasket kit.
If I understood Gary correctly, I need to have the hard plastic umbrella seals installed on my exhaust valves or there will be another failure.
Also if those are the correct ones, just to clarify they are supposed to be installed at the top of the valve under the retainer? I'm gonna have a hard time getting my machinist to do that I bet unless I know for absolute certainty that they are supposed to be installed up there.

 

[swampdigger]

With my kit I got 16 small plastic pieces, which go into the underside of the valve spring retainers. Eight larger plastic pieces, which slide onto the exhaust valve stems, and then 8 positive seals for the intake valves.

I laid my retainers on a bench, with the underside pointing upward, and used a flat piece of metal to press them in by hand.

 

[87crewdually]

My kit same as rangerwreck, as I explained in another post. Just for clarification you use either all umbrellas on intake/exhaust, / or posi's on the intake valves and umbrellas on the exhaust valves. You NEVER put both on one valve or spring will bind.

 

[RLDSL]

Standard is positive rubber seal on intake and white plastic umbrella on exhaust. The 7,3 came from the factory with positive seals on both intake and exhaust but it was ******* the exhaust guides so they changed it and all replacement seal kits now come the other way. Personally since I knew I was going to be running synthetic and wasn't worried about lack of lubricant in the guide, I put positive seals on both intake and exhaust when I rebuilt mine last time.