I've been waxing for a few years and won't go back.
Couple of tips-forget the ultrasonic, its really not needed.
A couple baths in fresh oms in a mason jar or similar to clean factory stuff off is better.
I "never" clean a chain after the initial prep-after 300 mi or so, I throw it in a cold crockpot, turn it on, and come back a couple hours later or the next day. You want the chain to be as warm as the wax for best adhesion. I use a bent coathanger inserted in chain prior to dunking to get it in and out.
The gunk and dirt comes off and settles to bottom. Throw the wax away after it gets too dirty, a few dozen uses.
Avoid KMC chains if you wax, they use a surface coating that the wax doesn't adhere to.
https://zerofrictioncycling.com.au/wax-instructions/ - site is filled with useful stuff.