Yes, change the receptacle to the one you presently need. Replace the 50A breaker with a 30.

Thanks bus_driver! The guy at the electrical supply house said the same thing, including changing out the breaker. he said the L6-30 didn't use the neutral so I should clip it back to the insulation, cap it and leave it in the junction box. I'm thinking I might call an electrician to do this just to be safe tho!

You don't need to clip it (you might need it in a future reconfiguration). Put a wire nut on it and stuff it back in the box. He is right that an L6 has only the two hots (and a ground).

I don't believe in burning bridges. Leave as many possibilities for the future as possible. .

He said "clip it back to the insulation" - I take that as just clip off the exposed copper loop - not the whole wire.

It is my practice to preserve that portion of the conductor. With 50A receptacles, it typically is necessary for all the conductors to have a definite length relationship to each other. If one is shortened, all must be shortened to be installed correctly.
So let me be direct--NO CUTTING OF THE CONDUCTORS.

I agree with BUS. Don't cut it at all. There's no point to do this and you may need that length in the future.