Put the 993 wheels on the Boxster and compromise...
I like the 993, however the chassis dynamics are no match for the Boxster platform regardless of how much Porsche obfuscates that fact to protect the 911 juggernaut. Your car is beautiful, I'd contact Jake Raby, extend your engine life while adding serious muscle to the engine. A superfast Boxster at a lower cost than a 993 replacement is my next move. In the resale market, anyone who does their homework will someday value the M96 corrections and if they don't at least you got to enjoy the performance. It will be a sleeper too, below insurance company and wise guy radar.