I have Aloha, and have added a center post. There said it.
I have so much respect for artwork and game integrity, but after much indecision I put in the post, and have been more than happy ever since. My EM purists buddies, admitted the game sucks without it. it's your machine, that was made on an assembly line not some holy relic.
IMO this game isn't much fun to begin with, It's brutal, even with out the out lanes. I mostly keep the machine to go with my other Hawaii themed games, and my wife is from Hawaii. After putting in my post i saw the plastic piece someone made for Ghostbusters, where a clear plastic piece screws above and over the flippers with an upside down post on it... Had i though of that I may have tried that first.
PM if you have any questions...