In fact, I remember when road and track, or car and driver, got so enamoroed with the good looks of the XKE and the bad reliability, that they had a project, and they took out the jaguar engine, and replaced it with a Pontiac overhead cam straight six, and replaced the Lucas electrical system with a Borg-Warner, and ended up with a great looking, great performing, RELIABLE XKE. Sometime back around the late 60's or early 70's - they ran a whole series of articles on their project car, and were very satisfied with it.
Check out www.jagsthatrun.com - they took the idea and ran with it.
The really scary thing is, I know how to make one run (a 68 at least) and when they run, good god are they fun to drive fast.