Just curious but are those the right lug nuts for those wheels?  Mag wheel lug nuts extend deep in to the wheel.  Mine barely stick out past the edge of the wheel center but they have plenty of thread engagement.

https://www.gorilla-auto.com/gorilla-tech-tips

In this episode I revisit replacing the wheel studs and fit the sway bar and bushings.

 

 

There are factory plates that go between the sway bar bushings and the frame rails. I think they help reinforce the frame rail and spread the loads out

In this episode I fit a 123 distributor to the 680g to hopefully get it running properly once and for all.

 

 

Did you install a new timing chain?

Yep.

I played with it again yesterday and I have actually figured out that the timing was heavily retarded. The issue now is that it's happy place gives me a reading of over 30 degrees advanced timing at idle, so I am wondering if I installed the drive shaft for the dizzy one tooth out?

Yes, it sounded like the timing is heavily restarted, do this: dial in the timing with a vac gauge ( it can be your best friend), keep advancing until you get a maximum vac reading, if you over advance it will start drooping. if the engine likes more timing then 15-20 static, chances are that the timing chain is stretched ( unless you installed a new one) or the cam timing is off somehow. Keep in mind that everything is relative and factors like fuel quality, altitude, jetting and compression will effect the ideal timing. 

57 minutes ago, Home Built by Jeff said:

Yep.

I played with it again yesterday and I have actually figured out that the timing was heavily retarded. The issue now is that it's happy place gives me a reading of over 30 degrees advanced timing at idle, so I am wondering if I installed the drive shaft for the dizzy one tooth out?

It might be that the timing marks on the damper are off.  Could be the wrong damper, or the wrong tab on the timing cover.  The early 240Z's used a different setup than the later 240Z's and 280Z's.  I browsed through the video but didn't see a timing light anywhere.  How do you know timing is at 30 degrees?

The actual timing won't be affected by where the distributor is on its drive gear.  Ability to set timing will be affected, but not the timing itself.

29 minutes ago, Zed Head said:

The actual timing won't be affected by where the distributor is on its drive gear.  Ability to set timing will be affected, but not the timing itself.

Exactly what I am thinking. The marks show that the sweet spot is over 30 degrees advanced, but that is just what is indicated, obviously not what it is actually running.  

The reason I think it is the drive gear, is because from memory it is about 12 teeth, so one tooth would be around 30 degrees.

Also just to clarify, it is a brand new chain and I tested the timing with the timing light ?

Have you had the timing mark on the cam sprocket, and the timing mark on the damper both at "zero" at the same time?  The distributor also has two timing marks on it that are often overlooked, two lines that will line up when timing is close to zero.  I stole a picture from a thread that stole it from atlanticz, below.

Also, the ZX distributor base is offset from the 240Z and 280Z base.  You might have a ZX base under your 123 designed for a Z.  I think the set screw is off about 30 degrees.

Stole another picture from zcarsource, but he owes me since he stole a picture of mine, of a rusty relay.

Yep. I ensured that was all correct. As for the base, with this distributor it doesn't matter, it will spin 360 degrees.