Great save, and great story. Yes, this is one heck of a great game.
Although it is a two-player machine, it is a true add-a-ball. The art package, backglass animation, features, and gameplay, make it one of the best ever. "Paradise" is also very good, but oddly, it seems to be more scarce than "PI".
I too have one in the restoration queue. It's the third one I've owned.
Picked it up at Pinfest last year. Although they allegedly produced only 235 copies of this game, I've come across three, and know several collectors who own one.
There have been a few offered on eBay over the years as well.
Gottlieb did produce an export version called "Hawaiian Isle", and who knows how many of them may still be kicking around.
The second one I owned started out with me as the lower box only.
A "car guy" friend of mine found it for sale in the back of a pickup at a car meet!
I thought it would be impossible to find a head for it, and was even entertaining the idea of possibly making a custom single player wedgehead for it. After about five and a half years, a lightbox for it turned up, and I was able to purchase it. That one now belongs to @mopar, who has never come across one on his own, despite finding some very obscure and esoteric titles.
Thanks to you for hunting down and saving this classic!

The adventure of the hunt is sometimes just as much fun as the game itself.

Is that the lockdown bar that was on the game? As you may know, it's not the correct one. It's supposed to have the narrow one with the cast metal end caps.

It must have been changed sometime much later since this type of bar did not exist in 1965.