boost flutter?

[Dan Simoes]

With my lehmann stage 1, I am seeing two symptoms on my analog VDO boost
gauge:
- boost builds and peaks at 15psi, pauses, then later pushes up to
18-19psi
- occasionally I am seeing a "flutter" of the needle at the top end, as
it goes between 18-20.

The flutter was cured by tweaking the wastegate as I recall?
I did that (5-6 turns) some time ago but undid it trying to fix #1, of
course I don't know how many turns I am at now.  Should I replace the
wastegate cap and start fresh or just turn it counterclockwise as far as
it will go to get back to "zero"?