I’ve just converted my DT 5.1s
I’ve used the Eclipse Tublesskit tape (same as the DT branded one, but cheaper), stans sealant and Bonty XR4 (non-tubeless) tyres.
Took a few attmpts, during which I learnt:
When sticking the tape to the rim, allow a few hours for the adhesive to go off. It MUST stay central.
I had to buy a decent track-pump, and made up a ghetto accumulator to seat the tyres – seat both sides at once to ensure the tyre sits on the tape correctly.
Then added a bit more sealent than officially required. The tyres were well-used so had a few holes, the sidewalls are porous as they’re not tubeless specific, and the bead was a bit worn from getting on and off from the numerous punctures I had been getting.
Rear tyre took about 2 weeks to get on, by the time I’d learnt that.
Front took 30 minutes!
stayed inflated ever since, and feels a much nicer ride.