Hi Paul,
As Vista suggests, I own an Apache from Jeff Uren's stables: Essex V6 3100.
It's very difficult to find any information on them due to the small number created. Whilst approx 1000 Cortina Savage's were made there were only 50 (ish) Apache's made and only 1700 [ish] cars made in total. I'm only aware of another 3 left in the UK.
Jeff Uren died in 2007. From what information I can gather sometime in the mid eighties when he started up an interior design company a fire broke out resulting in the loss of the majority of the "Race Proved" documentation.
As a car to drive, let's say it's got a "lively" back end. All the weight is in the front. It sounds lovely though and the torque is mental! Pulling off in 4th is no problem whatsoever. I'll get some pictures up