Yes, Alum will eat the steel, so strip the carb of all hardware you can, or lose it to the slow chemical reaction.
The carbs have a bit of Zamak like Zinc, Aluminum, Tin, etc. The white build ups behind pressed in or screwed in jets I think is a zinc compound. It is quite hard and the CV carbs really respond well to a good industrial ultrasonic bath. I could not believe how many baths and cycles my CX carbs went throught with the 2.5L Harbor Freight Ultrasonic cleaner. Get the warranty and have them replace it before your two year or one year warranty expires. The cashiers would tell you to do this trying to sell you the plan. Set a Google calandar reminder to do it the last month. They actually did honor a warranty that was a couple months expired if I would buy the product warranty for the new device... it was not the ultrasonic cleaner. I would really recommend you buy a larger industrial unit. It will have more transducers as well as better quality. The HF unit only runs for 15 minutes or was it 8 minutes... it is short and the heater is not recommended be used for more than 15 minutes non stop. It will stay hot enough after that for a couple cycles to give it a rest. Requires a lot of babysitting to run it for an hour or two, changing fluid frequently when it gets dirty. Also repositioning the items to change the point where it is concentrating of the transducer is most effective. You can map the transducer's strength in various areas of the tank with a sheet of aluminum foil vertically in the tank. This is a means of testing for transducer performance if youdo it in multiple locations in a repeatable grid the same locations everytime before you use it and keep records. Businesses often have these types of procedures every shift where the ultrasonic cleaner was used.
Sorry for the long reply.
David