First step:
As sad take lots of pictures first from the connectors (close up)
There are 2 strings of cable 1 is for the playfield one is for the cabinet.
If you only swap the playfield follow the cables and only remove those connectors.
Number each connector (left and right on the connector)
VERY IMPORTANT the ribbon cables have red lines they should be put back in the exact same order(red line up or down left or right and so on)
You can first place all the lamp boards and so to new playfield.
The strings of the playfields comes mostly in 3 or 4 strings.
You can start of for example with all that has the coils and what is attached with the coils.
Remove that string clean up and put it on new playfield.
Than the ones with the lamps (General illumination)
Then the switches.
This way it’s easy to do it.
I hope you understand what I mean
Go to YouTube and look up films of playfield swap.
The most important thing is as sad before lots of pictures and common sense.
Here a video to give you an ide
Good luck