Just a few minor mods (pictures attached) that I have made to my 1996 XJR.
1) I have fitted a small breather filter to the secondary air pump (not fitted to all models). This pump only operates for brief period of time on a cold startup so demand for fresh/filtered air is minimal. This mod eliminates the extra long hose across the front of the engine to the air filter box on the opposite side of the car. Less under hood clutter.

2)I have relocated the cooling fan relay from buried behind the bumper under the headlights to the body frame above the headlights where it is accessible together with the other relays. I have also fitted a single connector which makes disconnecting the fans easier & more accessible. Just undo one connector, undo the 2 bolts & lift out the fan. All done from the top, no underneath access required.

3) Oil catch tank adjacent to the coolant tank (just fits) It is connected to the normal cam cover breather & has an oil separator built in.It has been fitted for several years & I'm sure has alleviated much of the oil film buildup on the throttle body. The return hose from the catch can is plumbed in as per original.

John Herbert