Yeah, that old school nitro (definitely not standard, by the way) likes to cloud up if it isn't wiped down regularly. I generally use Dunlop No. 65 guitar polish, though there are probably people who have their own favorite cleaners/polishes that may be cheaper/just as good/etc. which may have been around since before my time (hence my ignorance). But that's what I use. It may take a few wipe-downs before the haze is gone. Hopefully you won't have to go to a polishing compound to get it glossy again.
*By the way, is that your Candy Orange Juice LG5 in your avatar? I've lusted after that bass for years!
Oh nice, and thanks for the response! I'll buy and try the Dunlop polish. My finish doesn't have any visible hazing, I don't think, so it should be more than good enough. Over the years, I've just realized that the finish is super fragile so I'm okay with any product that won't strip the nitro layer off the bass.
And yes, the avatar is of my current and only bass

. Back when I got it off another TBer, I don't think Jimmy called it the Classic Supreme, but that's what it essentially is I think. There was also another TB member who did a review on my bass for some magazine, I think, before it ended up in my hands. The review was raving, to say the least.
It's an amazing bass, and it's THE reason I've let go of all my other basses (MTD, Nordstrand, Roscoe). Not to put down the others I've owned because they were all great basses, but the LG5 just fit ME and the sound that I wanted.
I see that you're in San Diego (according to your profile), so if you're ever in the Orange County or LA County area, I'd be more than happy to meet you at a local music store if you wanted to check the bass out. Unfortunately, the bass has its share of tiny dings here and there that have seemingly appeared on the bass over the years, but it doesn't take away from the sound it produces!
I've attached some old pictures a friend took for me of the bass for viewing pleasure

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