How about making an arm that would go on the inside of the cabinet through the woofer hole?
You can center the arm then block from the arm to the cabinet inside. I would guess the production guys have a similar setup with the ability to spin the cabinet to allow easier access to surfaces.
Anybody know if there is any such piece of equipment, especially if the cabinet does not have the ability to pass something all the way through?
What I did was insert a length of PVC pipe straight through the cabinet on the X-CS encore center. (that I haven't yet finished). The cabinet was suspended between 2 auto jack stands that were covered with plastic bags to keep the overspray off them. The cabinets were able to rotate during spraying, exposing all sides. It worked out well, but it depends on the cabinets whether it would work for your project.
I can see how that would work if the cabinet had openings on opposite sides. I could probably use the pass through method on N1Xs and X-LS Encores when using the same flared port tube as with the N1X.
Since I like to use tube connectors instead of binding post cups that cuts down on the cabinets the pass through method will work with.
What did you use as the gasket material around the pipe?
I'm getting ready do finish a pair of LGK 1.0s so no pass through here.