I got a good deal and need advise

I got a deal on a 8 3/4 rear end for my 65 barracuda. I got the housing and a 489 cased sure grip with 3:23 gears in it. Sway bar and coil over shocks with some cool chrome traction barswere also included.
The center section has been sitting on a shelf for a few years with associated layer of dirt settling on it. Stayed dry, but not in climate control.
No rust showing on it.
I just want to clean the gears before installing in the car. Whats the best way to do it without taking the case apart. Can I just spray the whole thing with engine cleaner and pressure wash it ,case and gears?
Also, the sway bar mounting brackets were welded to the donor car and I couldnt get them off. I was wondering who would sell something like that.
Any suggestions on cleaning the rear end?
Dan