He isn't going to live forever. Somewhere down the line, he or his heirs will sell it. And even if they're up front about it, you can count on some subsequent seller misrepresenting it as a "super rare one of a kind custom shop special order Gibson." To me, that's just not right.
This isn't like putting a Gibson TRC on an Epi. This is a pseudo-mahogany Slammer intentionally concealed. The Hipshot bridge is worth more than the bass.