Anyone familiar with Defi racer gauges?

I came across a Defi white racer boost gauge (new and never installed) for a good price and picked it up. Have it all wired in and had a question about the dimming functionality - do Defi racer gauges just have two brightness levels - full bright for daytime, then a single dimmed setting for dimming? I have searched around a bit and have found folks that say there are 2 levels, and folks that say their gauge "dims perfectly" which could mean it dims when the headlights are on, or that it dims, and adjusts with the dimmer switch...

 

 

Currently I grab B+ and ACC from the fuse box with add-a-fuse things, then I have the illumination lead tied to the violet wire (grabbed the one going to the parking brake illumination since I had a harness I made and could splice into that instead of factory wiring)

 

 

So is this the correct behavior? I believe some of the fancier Defi gauges behave similarly, but you can adjust the level from the control unit (which the racer gauges obviously don't have)

you can buy the control unit?

No - while the Advance series gauges require a separate control unit (which allows you to adjust the illumination intensity for bright/dim for some of those gauges), the racer series gauges are standalone units - there is no control unit. There are no buttons/switches on the gauge, either - you have switched power, constant power, ground, and illumination. As far as I can tell, when it sees voltage above some threshold on the illumination lead, the gauge flips from the day setting to a dimmed/night setting. Others I have reached out to indicate that there are only two settings, daytime (full bright) and night (dimmed to maybe 30-40% of the day brightness) - I was trying to see if there was something I was doing wrong that was yielding the 2 stage bright/dim instead of dimming with the dimmer.