I went through all of the literature that I have, and unfortunately found no mention of either of these options. I have a copy of the "Accessories Installation Manual" that was sent to dealers. It could be that these two options were deemed too simple to need instructions for...although the electric shaver is included!
In the "1951 Chevrolet Engineering Features" Catalogue, there is mention of a Portable Spot Light, but the description sounds like it uses a hook or hanger, not a magnet. There is no part# included.
Good Luck on getting any info... if anyone has a picture of either of these items, or a complete list of all options, I would like to see them as well. My '51 has quite a few options... but there's always room for more!

The service lamp had a little red plastic shield with a magnet on the "bulb" end, a long cord and a male plug the went into the cigar lighter for power. I have one of those.
For the life of me I can not recall the steering wheel cover. It was only available in 1951 and 1952 and they were packed 6 to a box.
Both of the above were new for 1951. The light was available for many years later.

Speaking of 1951 accessories.....

What about tail lights (or maybe called turn signals) sort of outboard on the rear of station wagons.

I've never seen them in original ads or Chevrolet illustrations; but see them all the time in the "flesh." One on each side of the rear of the station wagons.

They look a lot like 39 Chev tail lights.

Are/were they dealer installed or aftermarket or what????

Bill.