Radio Install

[73runner400]

I'm installing a new to me AM/FM stock radio I got from Ward's classic car radio. My car, since I've owned it has never had a radio. How do I install it? I have the side bracket but I can't get the radio to stay tight. Is there another bracket or am I missing something? With the radio installed, no sound is coming out of the radio until I jump the ground wire. The dash harness is new, the radio is restored, and the speaker is new. Does the radio have an internal ground that is supposed to ground to the dash when the radio is installed?

My car is a 73 Roadrunner.

 

[moparmarks]

There two nuts on the shafts under the knobs
The strap in the rear
A screw on the right side accessed through the ashtray hole.
Mounts are the grounding path.

 

[73runner400]

Where can I buy the knob nuts?
The strap in the rear, is that the side mounting bar that mounts to a rod/pillar/bar on the dash?
What screw through the ashtray? I took the ashtray assembly out and don't see any screw. Do you mean the place where the radio side bar attaches?

Thanks very much.

 

[moparmarks]

I can see if I have any extra nuts. Ward didn't have any?
You have to pull the ash tray housing, 4 screws, to access to the radio screw.
Here is a pic of the backside. Radio strap goes to the dash strap. Can't see the side screw in the pic but is front of the long strap next to where my speaker connector is sitting, I think, been awhile. May be higher. Pull the housing and you'll see where is goes.

- - - Updated - - -

Found some more pics.
Here is a cluster. See the leg with the hole hangging down in the lower left? Thats where the side screw goes.
Here is another pic. See it next to the ash tray?

 

[73runner400]

Thanks for your help! I was trying to find that pic. I removed the ashtray and the screws and the housing, I can't fit my hand back there to get that top nut. I looked for the radio knob nuts on ebay but the only ones listed were GM ones. Would those work? I have my radio quasi installed but no luck on it working unless it is grounded by a jumper. I would think that it is grounded enough for it to work...