I guess I'm a bit confused trying to follow everything you've posted, but as I said way back in
this post, the tail lamps, side markers and dash lights are all fed by the same circuit, which is black with a yellow tracer. Then
here I told you, "If you have taillights and side markers, then the problem
has to be dimmer-related. It's either a faulty switch, the switch is not connected, it's not being fed by the headlamp switch, or you have a broken wire somewhere along its run."
I cannot, for the life of me, understand what you've been doing since. Why would the fuse box come into play, if you have tail and marker lights? The working lights are literally on the same fuse as the non-working lights.
I asked you to test the dash lights by running a jumper wire from the red triple tap to the orange one with the key in the RUN position, which would've told you immediately if the problem is at the dimmer switch. If the dash lights worked, then either the dimmer is faulty, it's not being fed by the headlamp switch (very unlikely since the exterior lights work),
or there's a broken wire. You found a broken wire and fixed it, but for some reason you continue to probe wires. Worse, you're doing so without using the wiring diagram to see where the wires you're testing actually go in the circuit... without ever checking to see if fixing that wire solved the problem. Why?
Here's what I do when I find a broken wire: I fix the wire, plug everything back together, then see if the problem persists. Why make it harder?
If that didn't fix the problem, the factory wiring diagram tells us the function of all five wires on the back of the dimmer switch:
- One black/yellow tracer (BK/Y*) comes from the headlamp switch. It feeds directly to the dimmer switch. Inside the switch, that voltage travels through the rheostat to the tan (T) output wire.
- The other BK/Y* at the dimmer switch is 12V+ out to feed the park, tail, and side-marker lamps.
- Each yellow (Y) wire feeds one of the door switches, which is how it overrides the dome light without opening a door. Those two wires are fed by the rheostat when it's clicked at the end.
- The tan (T) wire feeds the orange (O) wire for the instrument cluster/console/radio lights through the fuse box.
Since all the fuses are good, and the park, tail, and side-marker lamps all work, that means either you've got a bad dimmer switch or a broken wire. The broken wire you found and repaired is
BK/Y*.
Until you've proven otherwise by immediately testing after fixing that wire, there is no reason to believe any other wire on the car is a problem, or that the problem even exists anymore. Why you've continued to test after finding an obvious problem and correcting it, rather than immediately seeing if the issue is corrected, is beyond me. You're literally searching for a problem that may not exist anymore.
Quit jumping around. Solve one problem at a time. Once the dash lights work, worry about the radio or the vacuum leak. Every time you leave a task, you lose track of where you were, or what was next, because you lose your focus (which is true of most people, myself included).
On the good news side I have radio, on the bad, it won't tune to my station, I'll fight that later.
It actually takes a few minuets to warm up.
The ariel is defiantly NOT stock, at least not for what I had, a one piece mast even shorter by a little than this one down!
The antenna you have is 100% correct for a 1974 'Cuda--
with an AM radio. Cars with an AM/FM radio, like your original 'Cuda had, used a fixed-length (31" overall) mast, part number 3513745. You simply ordered the wrong antenna. The good news? If you want to use the solid mast, you can change just that easily enough, and virtually any non-black Mopar solid mast from '72-'89--including trucks, vans, and FWD cars--will work. There's no need to disrupt the base; it's the same for either mast. The bad news is, new ones are nearly impossible to find. The original part, 3513745, later superseded to 4469014 but there don't seem to be any of those out there either.
If you simply want to stick with the telescopic AM mast, simply set its height at 31" from the base. I don't know if you ever listen to AM radio, but out in the middle of nowhere you can pick up stations from hundreds of miles away with that mast at full extension. The downside is that the telescoping masts are ridiculously easy to break.
Do not buy anything listed on eBay. I found nothing I trust. If you want a solid mast like your old car had, let me know. I haven't got any spares at the moment, but I have a friend that might be able to help.
this keeps happening when I push down on the hood to see if I'm set at the right height! 
The straight lines are close, I was able to move the fenders over about 1/8" could have used another 1/8 but slots were maxed out. 
Now in shimming the fenders to try and match the hood, up in opposite corners I came close, but that raised the fender way too high, if I can get that bolt in from the bottom by the door it may pull it down a bit?
Other side I got the gaps better, curves are still off, but that ain't changing.
