Graham - the IMS set-up on a 986 and early 987 Boxster is the same as the 996 and Gen 1 997 so the fixes are the same. The "Mezger" engine in the Turbo, GT3, GT3 RS and GT2 RS has a different bottom end borrowed from the GT1 race car and has no problems.
The attached was taken by a staff member at OPC Glasgow because coincidentally three generations of 911 (my 996, and customers' 997 and 991) were lined up in order outside the showroom.

Don.