From what I can gather from the very comprehensive history (almost every receipt and MOT from new, all in date order in a folder!) she was owned by a lady in Cambridge, Olga, for many many years. She was very well loved and has had lots of money spent on her, including regular services and maintenance, and a recon unleaded engine over 20 years ago, which has to date done 49k miles.
I'm not sure what happened to Olga, but in recent years she was owned by the lovely family that I bought her from yesterday. She seems to have been lacking in love and attention recently though, and at one point was covered in handpainted flowers, which have since been sanded off.
Most of the work required seems to be cosmetic - the wood is sound (but I'm going to sand and re-treat), the floors, chassis, inner wings, engine bay etc all appear solid with no areas of concern, the seats are in excellent condition, the carpets need cleaning/replacing. Three of the four wings have dinks and dents, as does the driver's door, but the sills and door bottoms etc all look and sound okay. The chrome trims/badges etc all need tlc/replacing. The engine runs sweetly, and I've rediscovered the joys of a manual choke!

She's already booked in with my mechanic for the once-over and a brand new MOT, then it's off to the panel beaters/paint shop for quotes to help me decide whether I need to replace any of the wings, or if the dents can be nicely fixed.
The list of jobs is growing, but luckily I paid a great price for her, so have a decent budget to bring her back to life (unpleasant surprises permitting!).
With a deadline of 25 May, I'd better get started!
Thanks to everyone for all your help and support whilst I've been searching....the journey begins in earnest now!
