First the Car:
A 2001 Vauxhall Astra Coupe. It's a 2.2 litre bertone model. Engine code Z22SE.
This caused me a problem straight off, as the engine is quite unusual, not rare or anything, but it appears that most people with this engine aren't too concerned about mpg, and would rather have performance. Unfortunately, I bought this just before petrol went stupid, selling it would probably lose me money so I decided to go the lpg route. (Plus I quite like the car.)
Regardless, due to the above reasons, many lpg converters had never seen one before. Likewise with Andy at warrington autogas (slighlty concerning). However, a couple of people on the engine forum http://www.z22se.co.uk/ have had theirs converted, so I knew it could be done.
It's a bit different to most transverse (sideways mounted) vauxhall engines, in that the air is taken in the front, with the exhaust manifold exiting at the rear of the engine (seemingly the most natural layout?).