Thanks Gramps. Been wanting to find this info.
The MK's have a 5 on 4.5" (114mm) hole pattern and 39mm (1.535") of offset on the 16X6.5 rims which = approx 5.25" Backspacing. See chart and more info here: https://www.rsracing.com/tech-wheel.html
The XJ also has a 5 on 4.5 hole pattern but the backspacing depends on which wheels you find.