Can I get some pointers on a boost leak test?


I have a new to me 03 C5 RS6. Has intercoolers, apikol intake and a stage 1 tune. ZERO boost. Replaced one hose I found with a smoke test, but I think there are more issues. I was told possibly a passenger turbo is out but I should still see something if driver is still good. Trying to get a baseline for what to replace when I have engine out. (Everything is not an option right now).
I know how to do a leak test on my 2.7's, I am probably over thinking this 4.2


I have plugs for inlets, air source to passenger diverter valve hose. Plug diverter valve, remove oil cap. When doing that all air escapes oil cap. Do I need to remove a PCV and plug that line to hold air?

This car is a mess and I need to get a good baseline of issues before engine pull.

Thanks!