I was afraid you'd ask that. ;-)

There's a bunch spilled down the label and I can barely read it. *scrape, scrape* Valspar Stainblocking Bonding Primer | Sealer -- Extreme Adhesion. Lowes product #46620. I used a light coat, covering all surfaces (including the annoying grooves in the paneling - a roller with a higher nap helps here) but definitely not producing a uniform white after primer alone. Instructions say not to dilute, but I did a tiny bit--this made the paint roller very drippy... but the final result looks great.

I did something similar recently on similar vintage paneling. I used a primer specifically rated for wood application.

To seal the deal, so to speak, for the top coat I used a high-cover Valspar 4000 and it worked great.