Any experience with stud tail?

Hi guys me again I may have asked this a long time ago but I have a really super bad memory. Has anyone had any experience with stud tail on a neutered male cat (My Boo) and can anyone offer any gentle ways of cleansing it off short of popping him into the tub and giving that tail a good wash? He is lion cut shaved for summer and I have shaved his entire tail except for the very end, leaving a puff. But you can see the blackhead looking things, and the oily feel. He's had it since I can remember, and the vet insisted it was one time ringworm YEARS ago, and the ringworm meds didn't make it go away Then I learned about stud tail and it looks EXACTLY like what he has. It doesn't bother him, though. If I scratch it he enjoys it a bit, but he is sensitive about his rear area anyway. (This is Boo we are talking about here, white Persian with CRF)
I've tried baby wipes, should I rinse them in warm water to get the Aloe and Vitamin E out first? (What I do now) They seem to help a bit but do not clean very well on his tail. I tried a small patch with an alcohol swab, which he didn't mind but it did not clean it too well either. The only thing (back before he was dx'd with CRF) I used was Head and Shoulders Maximum Strength dandruff shampoo and it cleaned his tail up perfectly. It took a week or two for it to come back too. Maybe 3-4 is more like it. But I am not using that on him, not with CRF.
I remember it disappearing completely after his bout with Struvite crystals and his hospitalization at the vet after bladder and PU surgery. I always thought it was an antibiotic or something they used for something else that made it disappear. But then it returned a few months (I believe) Later. Any help is appreciated. Thanks guys. And I'm also going to ask my new vet about it when I call her in the morning to see about other tests.

Interesting! I put my cat in the bathtub with just a little warm water to cover his feet and used baby wipes between his back legs and belly and then on his tail, too. Lots of gunk came off! It was black at first. Then I finished off with an alcohol swab on just his tail. More came off, but there are still blackhead looking spots on his skin. I washed the alcohol off (or it dissipated before I could, anyway, but it's ok) and washed it again with a baby wipe so as not to dry it out.

I used a washcloth too. Thanks for the info I will ask my vet about it and see if she's heard of it!

Also, have you ever seen it spread from the tail to the very back edge of the rear legs? Like down the ankle? I see it back there, too. But on his inner thighs on his back legs he has a bit of black, but then there is an orange tinged dirt/wax stuff.. have no clue what it is and it is SO DIFFICULT to get off!

Thx for your help

Just for added clarity here are some pics I was lucky enough to get!




This is after it was cleaned up a bit but is still a little dark:

Thank you so much.

Thank you.

Has anybody ever heard of stud tail being diagnosed as ringworm? I don't have a black light handy but years ago it was diagnosed as such because it lit up in the black light. But I know, also years ago, when I shined a black light on my face, all my zits lit up. I know he doesn't have ringworm (The meds they gave us didn't make it go away) so was just curious.