Searched the usual sites but couldn't come up with anything specific to the B5 S4, or even with a twin turbo setup?

I've boost leak tested my DSM a billion times but the setup was much more convenient, just pull off the air filter and cover the actual turbo inlet with the tester to diagnose.

I can only imagine that since we do not have access to the turbos that the only method would be through the Y-pipe opening?

Thanks.