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Heres the under the hood pic. Does anyone understand the OD function? I’m buffaloed on how to work it. It’s at my mechanics shop now for the check up before I start to drive it, routinely around the neighborhood.

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Thanks I’ll share the maintenance specs with my mechanic.

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Overdrive is a very valuable feature that will add a lot to your enjoyment of the car.
When the overdrive knob (to the right of the steering column) is pushed in, the overdrive is usable. When the knob is pulled out, the overdrive is locked out of use. You will want to leave the knob in for most driving situations so the 4th gear can shift in and out. I do lock mine out when driving in the mountains to have increased engine braking.

You can run up through the gears like any other transmission. At about 20 mph or so the overdrive becomes available and you can shift into it at any speed you wish by merely taking your foot off the gas for a moment. You will feel it engage if you pay attention. If your speed drops below about 18 the overdrive will disengage and you will notice the car coasting.

At any time while in overdrive you need to accelerate quickly, just tromp the pedal to the floor and the trans will instantly change back to 3d gear. Lift your foot off the gas and it will shift back up to overdrive again.

There is some remarkably bad advice about OD on the internet and people will tell you all manner of goofy things. I will only mention two points: the car should freewheel below the OD engagement speed. If it freewheels above 25 the OD is NOT working properly. That will usually be an electrical issue.

The second goofy advice is that you must always pull out the OD knob before you back up. Not even remotely true.

Try out your car and let us know how it goes.

I would add that it is important to be sure that both the transmission and the overdrive unit are kept filled with the proper lubricant. The overdrive will be damaged if the car is driven fast without the proper amnount of lube in the OD unit. There are two places to check the lubricant level on an overdrive transmission.

Your car has the Electromagnetic Clutch and Overdrive option. There is a button on the dash labeled "Clutch" I've got the same configuration, it doesn't work and after looking in the service manual it is a complicated piece of engineering. Have you checked for the build sheet that would be taped to the top of the glove box? the build codes are "OD" and "EMC".

Gee thats the best explanation ive gotten so far. This came eith the car.

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Ok ill check it out and get back to ya. Thanks !!

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Ok thanks what kind of fluid goes in the OD vs the tranny?

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90 weight GL-1 rating in both trans and overdrive.

One has to watch how they work on old chrome, as if not right, you'll haze or scratch. Especially if you incorrectly used a buffing wheel. Almost impossible to remove haze causing by improper buffing. Always best like dealing with old paint to start low and get more aggressive as needed.
Since it's 3 layers, you have to assess what the issue is. Iron/rust stains are the base metal coming through so that means the three layers are damaged/porous. Vertigris/green stuff is the base copper oxides.
Pitting is not going to come off - they go all the way to the base metal. About all you hope to do is flatten it as best one can but that requires the edges to flake off and leaves a "sore".
If it's dull, then most likely the chrome has worn off from years of "polishing" and the underlying nickel is showing.
We've had all sorts of "home" remedies/stories since they started putting lots of chrome on cars. CocaCola and crumpled aluminum foil was big post war. I don't fall for these, nor agree with some of what's been said above...aka;hearsay.
The best thing I found, which is no longer available, is Simoniz chrome cleaner. I still have a part can that I hoard for special occasions, but nearly exhausted.
I wish there was a magic or easy method, but experience goes a long way on what to expect. Elbow grease is the other part. We learned as kids collecting what are now vintage hub caps off the side of the road/trash and cleaning them up. About the best case is when the remaining good can be polished bright to out shine the bad, aka; driver quality.
By all means, wax it once it's shiny. Most all the carnauba waxes will do, harder is better, but need to be removed and reapplied regularly. I've successfully used Nu Finish on chrome, but it's a drying to powder material and careful to apply and requires detailing to get the white stuff off, it'll go into pits. It lasts a year or so. You'll find many a car with lots of paste residue under the chrome which holds moisture. These new fangled silicon polishes are very hydrophobic but don't live up to their reputation on life expectancy over cost, in my experience. They also require re-application and are harder to remove.
ps: from the window sticker, the cost to re-chrome all that is multiples of what you paid for it. I spent that much just on the trim, a decade ago. I just went through and still succumbing to Biden sticker shock on a few pieces I sent out last month.