Hello out there, hope everyone is safe wherever you are. 

I have a MTB specific question. I want to take an older bike of mine and make it tubeless. I know that I will need tubeless compatible tires, rim tape, sealant and valve stems. The only thing I don't have is tubeless wheels. Is it trial and error to see if my non tubeless wheels will hold or not? Or should I start shopping around for a set of tubeless wheels? (I am also looking to go mullet with a 27.5 up front) I am looking for success / failure stories honestly. The type of riding for me is not extreme at any level but I learned that fixing a flat on the trail is more of a bummer than the road. The bike is a 26er with disk brakes and aluminum rims. Any advice would help out. Thanks for your time.