1985 302 valve stem seals

[SageSVO]

Trying to replace valve stem seals and my stock 85 5 L notchback… What seals do you guys recommend? Don’t really want to use umbrellas. I have some GT 40 seals with the right diameters for the valve and guide, but it’s not deep enough to seat on the head. Is that a big deal? Could I use them anyway?
any advice is much appreciated !

[bwguardian]

You are dealing with the old versus new style valve seals. They may make the newer style to fit the older head, but you need to make sure what ever you install fits correctly.