This being the first LS motor I have redone so this is probably a dumb question, but I bought a Fel-Pro full gasket set from Summit and the valve seals they gave me are not like the ones that were on the heads, they do fit the valve guide but don't have the shoulder that the spring sits on. This would change the installed spring height and have the hardened spring just sitting in the aluminum head spring pocket. So, wrong seals, even though its the set listed for this motor? and if so where to buy the kind like in the picture, GM only?

 

The seal and seat are two separate pieces on the older motors, that's what it looks like you got. You need the newer one piece style, 2001 and up I believe.

 

Just got in touch with Summit, they are sending me the right ones, the kit I ordered said with .492 valve guides, which I have, which both seals fit, but to use the 2 piece I need to buy spring locators, 36 bucks, which don't come with the set, or even noted in the product description, and they don't even offer a gasket set with the top hat ones included.