Was remembering a modification that Kirby mentions in the Book to make the bleed screw a bit easier to work with by cutting slots in the head for screwdriver application instead of via a wrench, and saw this item on Amazon. Although it says it is for various BMW and Mini Cooper models, note the dimensions (0.9 cm. o. dia/threads x 1.8 cm. overall length x 1.6 cm. dia/head) and wonder if this would work also for the XJS (in my case, '92 5.3).