[klondike98]

800 resistors....   yes, you did not pick the easiest radio for your first restoration.  There are folks out there who restore vintage radios if you decide to go that route.  If you DIY you will need a good readable schematic.  You can order docs here for just a few bucks. A free dowload can be found here but its difficult to read.

Electrolytic caps do not always have the negative lead connected to the chassis.  In your case cap 78 neg lead is connected to the center tap of the power transformer and thus the can is insulated from the chassis. Cap 77 however has its neg lead to chassis ground.  Also note the two 0.01uF caps in bakelite block #85 should be Y2 safety caps.  You can read about safety caps for use on power line input here.

You check resistors with an ohm meter one at a time.  In many cases you can just put the ohm meter leads across the resistor and check it but if there are other paths for DC current then you must unsolder one side of the resistor and then check it.  As I mentioned, some folks just go ahead and replace them all with modern resistors of the correct value.

Here's a good read for beginners