Do you have Authentication on the signatures? There are a lot of fakes out there..... Not saying yours are fake, but, at those price projections, I hope you have proof!

Wow pinballwizardz....sorry about your disability. I don't know what it is but I hope you are doing ok. I appreciate what you are trying to do for your dad...I recently lost my dad and I think about it every day.
Keeping it real, you have to understand where everyone is coming from. I too have a SWDE and it is in great condition, believe me, I hope yours sells for 20K as that only makes mine worth more . In reality, your asking price is way out of whack! I think as other posters have said, you might be better selling the autographs separate. I don't think you will get anywhere near your asking price regardless of your intentions. I find it a little frustrating that you ask so much...that it not what this hobby is really about. Like others have said, no one on Pinside will buy your machine, now you are trying to take advantage of an uneducated buyer...I know people can argue that buyer beware, but what if they are trying to buy a SWDE machine for their dad? Isn't that a little unfair to take advantage of them??
Perhaps, if the AC/DC machine is what your dad really covets, you can part with your SM? You'll get closer to the new price.....