I went in December to BAR in Modesto at the Western Campus of the Modesto JC and they were very courteous, informative and helpful...not to mention that they passed me through without a hitch
) Had to trailer it up and drive it around to their testing station in the back but it all worked out fine. Seems they were used to doing the SPCNs and were at ease with the process. Told me by just how much I was running a bit rich as an aside.
Good luck with your licensing - it's worth the headache!
Dirk