If you don't have a Revocable Trust with "pour over wills" then that's step one.
Pinball machines are "personal property" and will get split according to Will/trust without the necessity of probate. Not titled assets.
You should create a "personal property memorandum" PPM which acts as a codicil to your Will and dictates where your golf clubs, china, pinball machines, etc. go and to whom.
Sign and date in your own handwriting, no witnesses necessary.
Change your mind? Tear it up and do another one.