How to center a steering wheel...

[NIck Miller]

Slight negative, in my experience.  But that's on a miata, which is a very
nice SLA double wishbone type, with a bit of angle on the top control arm..

But usually -.5 to -1.2 for better handling, as it aides in cornering.
Perfectly neutral is better for high speeds though.  Like 120mph and such.
Unless you are cornering at 120, then it matters very little.