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Rules tend to be unhelpful, because there are too many exceptions… but…

First, the pipe carrying the steam to the radiators has to be pitched to allow the condensate which it also carries to drain. It can either pitch back to the boiler or away from it. But it has to pitch.

At its lowest point it has to connect to a pipe which will carry the condensate back to the boiler. In your case, that is the pipe which you want to move. That pipe can either be high, but lower than the pipe carrying steam, in which case it must pitch back toward the boiler where it can drop to the boiler, or it must be well below the water line of the boiler — preferably at or near floor level. If it is low, it doesn't need any pitch.

The air has to be able to escape freely from the pipes. That is called main venting. Where the main vent or vents is placed depends on how high that return pipe is.

The boiler and burner appear to be from the 1940s or so; there is no sign of piping alterations so they are probably original to the house.

Those old boilers were originally designed to burn coal and were built like tanks, but it is probably 80 years old, has undoubtedly suffered from corrosion and is not worth repair or additional investment. The burner is obsolete and inefficient; the motor is almost certainly shot and other parts will be hard to find. You would need a new oil tank as well. If the tank is underground, it may have leaked and then hazardous material remediation would be needed.

If you want to keep the steam, a new boiler correctly sized for your existing radiators— which the contractor should measure —and installed by a steam specialist would be a better investment. If you can get natural gas service, you will not need a new oil tank. You could run a steam boiler on propane, but that is an expensive fuel in most eastern markets.

Unfortunately few contractors in your region understand residential steam. Have you tried the "find a contractor" link on this site? I believe there is at least one steam specialist in Virginia.

Do you mean you plan to run it waist high? It's at head height now, right?

Waist high is not good. You don't want it near the boiler water line. Far above it, or far below it is what you want.

A 2' wrench or even an 18" from harbor Freight is cheap and with a cheater pipe it will do anything a 4' will do an a lot easier to handle.

If it is a return it has to be under where the steam condenses in the main and the emitters, the water can't flow up hill.

If you raise the pipe it will probably trap water and you will get water hammer. But we need pictures to tell for sure. Chances are if it could be raised the original installer would have done that

@mattmich and @ethicalpaul , the other part of the equation is……. balance.

You want the steam to reach the ends of all the mains, not only quickly, but also at about the same time. Once you accomplish that, the steam is available at every tee where a radiator connects, and will rise to all the radiators at the same time. Balancing the heat in all the rooms is easy when you do it this way.

This is where "pipe math" comes in. Once we know how much air is in each main, we have our starting point for sizing vents. Occasionally we need to make changes from the original sizings, but having that starting point gets the job done faster.