Quoted from Yelobird:Have to say your going to have a Really tough time trying to do a cabinet re-decal with it upright like that. Just take the time to pull the backbox and do the cabinet on the floor on its side. Much easier Especially when its time to apply the art. Use a simple orbital sander to finish that last bits and make is smooth your almost there.
Separating the head and cabinet isn’t too bad. Just label your connector and take pics. I did mine over Christmas.
https://www.flickr.com/gp/mrmikeman65/016Y5D