250-500cc When does it end ? Exhaust valves

I ordered a new exhaust valve guide block assembly. put it all together and upon startup I hear a exhaust leak. Seems the guide block differs from the one i had. Could owners with 360s verify which type they have, maybe I just was given a mal-manufactured guide block. I've check part numbers from 92 - 02 and they are all the same 8000-70642, please don't repost the pics with replies.

New.. notice the gasket sticking out and the exhaust gas residue


Old... notice the ear that would cover the gasket

I looked at mine and it has the flange like your original
where did you get the block??

take the gasket off an rtv sealent the thing on. the block looks the same as my 2002. but the gaskets cut on mine perhaps you got a different gasket with the block?
was the original block knackered then?