Hey SilverBob, that is one heck of a tumbler you have there.
That should get the job done!
You could also do your laundry in there in case your washing machine every goes out. Ha! Ha!
For me it is as simple as boil some water in a pan, add an excessive amount of automatic dishwashing liquid to it, let coins soak in it in a colander. After the water has cooled a bit just start swishing the water about and the coins against each other will remove the dirt so to be able to send the money to the bank. I have yet to be rejected at a coin sorting machine
I have a Myford lathe in my garage and gripped a plastic screw top fruit jar in the chuck,put the clad in with some coarse building sand,soap and water and set it off in bottom back gear(nice and slow).
When I took the coins out they were nice and clean but covered in lots of scratches. Obviously the sand was too rough and I will need to try something less harsh.
All my clad goes into the coffee machine at work !