From a guy with years of experience doing this first off all I can say is "good luck". Regardless of how you do it or what you do you will find it takes hundreds of hours to deal with something like this.
If the art is nice on a playfield you are likely better off selling it whole (as it sits) but from my experience once you start looking at them closely you will find only a low percentage of them actually have good art on them. Even if they were nice moving them like you did likely created some damage to a lot of them. (I am not faulting you for the way you moved them but there is really no great way to transport dozens of playfields).
The issue with selling them whole is shipping is insanely expensive. Boxing them is a PITA and packing supply cost add up quickly. And it that isn't bad enough most people will not want to spend more than a couple hundred dollars for a decent playfield (including shipping) unless a machine has some value. In other words who is going to want to pay $300 plus shipping for a nice fully populated Flip Flop playfield plus another $100 or more shipping when a nice Flip Flop machine in working condition is only worth $600?
On the other hand parting them out with take hundreds of hours and an average playfield only has about $300 worth of parts on it and in most cases that is a stretch. I have done hundreds of them and it really isn't a money maker!
As you have already found out you will be getting dozens of emails asking for specific parts, specific playfields, etc, Next people will start bitching because you didn't get back to them - or because of the fact they really wanted something and you sold it to someone else - etc.
Something like this seems like you struck gold but in the end you will find you killed yourself for nothing. Don't get me wrong I find doing these parts very rewarding - the issue is people just don't understand how much time & energy it takes.
In any event if I can help you in any way feel free to PM me. I have ZERO interest in buying more - I already have too much - but I will gladly help you if I can.
I have the same issue here not knowing what to do with dozens of beautiful fully populated playfields I have accumulated over the years. The "rough ones" are easy - I just make them into parts and list those parts on eBay. It is the nice ones that I find are the problem. You can't take them to shows without risking damaging them, I don't want to deal with packing and shipping them, and I hate to part them out since they are nicer than the playfields in 90% of the machines I see at shows. What the heck do you do with those?
FYI - almost every playfield is marked somewhere for easy ID. Some are marked under the apron and others are market under the top arch.