Cleaning Circuit Boards & Chassis

[AUdubon5425]

Well, I'm taking my first dive into cleaning a chassis.

I pulled the back off of this little '71 Motorola 12" portable, and it was obvious water had been leaking through the top at some point - and it was a smoker's set to boot. I couldn't visibly see what shape many of the resistors were in.

So I pulled the chassis, leaned it against the fence, and soaked it with Simple Green.

A toothbrush helped, but light water pressure sufficed as the Simple Green did most of the work. Now it's in the sun drying out.

Many of the tube shields have rust on them. Should I be concerned with this? They were soldered to the board so I haven't disturbed them yet.

Also, I found no markings where this was made. Was Motorola still manufacturing these small sets in America in 1971?