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Schould I be adding Lead substitute in my Gas? I have. Will it hurt? Can you add too much to a tank of fuel.I do not know if my engine was rebuilt or not.
Thank You

You should not need any lead substitute or other substance. Your car's compression ratio is not that high and when your car was designed and built they did not put very much lead in the gas.

The high compression engines that require leaded gas, were just coming in when your car was built.

It can't hurt to add a little upper cylinder lubricant to the gas. Redex, Marvel Mystery Oil, Bardahl or your favorite brand. Some prefer a shot of 2 stroke oil. It might slow down wear but is not mandatory.

In hot weather some find that adding 5% or 10% kerosene or diesel to the gas prevents vapor lock.

Another benefit of lead in the old oil and gas was to lubricate the valve seats. If your car has been rebuilt lately they may have put in seat inserts that do not need the lead for protection.
Packards do not need the anti knock qualities of leaded gas due to their lower compression ratios . The octane of pump gas achieves it's octane now by adding 10% to 15% ethanol.

That is what we need to be concerned with now.

Before 1955 most cars came with hardened valve seats and hard valves. The lead content of fuel was low, some brands had no lead at all. It is the high compression OHV engines from 1955 to 1970 that suffer from non leaded fuel because during that period gas contained large amounts of lead and engines were designed accordingly.

Before 1955 most cars came with hardened valve seats and hard valves.

For all the years and engines I'm familiar with, Packard did not employ induction-hardened seats or seat inserts, though they did use austenitic alloy for exhaust valves. As has already been noted the tetraethyl lead did increase anti-knock properties which isn't of particular importance to Packard owners, but the other property that lead imparted was for valve face and stem lubrication, especially needed for exhaust valves to minimize seat battering and recession if an engine is going to have a regular diet of high speed driving. This is the reason most good engine rebuilders suggest installing hardened exhaust valve seats. I think Chrysler was one of the first to use hardened exhaust seat inserts in their sixes, perhaps even pre-war (same war you're thinking of Rusty), but did not use them in the Plymouths & Dodges.

It's been posted many times here before, but let me again post a guideline chart about valve-seat recession. I still use TEL in my 56 Carib which sees a reasonable amount of Interstate speed driving. If and when I do a valve job I'll have hardened seats installed (available from NAPA) and be done with the TEL, you really need to use proper personal protective equipment when dispensing it.

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Did I hurt anything by putting in the lead additive? I will not put it in again. What range gas schould I use 87-89-93?
If I add m.m. oil how much for 10 gallons?
Thank You