Happy Birthday to the Vw Lupo. The first Vw Lupos where registered 20 years ago today. Out of the first 4 5 press cars to registered. Only one survives on the road today. Happy birthday T62DBW.
Short between centre brake light cable and rear wiper cable at hinge point in tailgate... common problem. The cable can fail in many odd ways in there. Unusual for the front wipers to go though.
Or... like @LR5V mentions, could be in the stalks. There's a "how-to" fix stalks somewhere. It's the front wipers that has made me suspicious.
Being the short stroke 1.7 crank, I'm very interested to know what the power curve is like, still using stock cam (i'm guessing)? Is it quite revvy like a petrol or just like the stock tdi? How did you deal with the injection timing? The pump and injectors are good to about 190hp ish. But like you say, if that torque is dialled back a bit to move the power higher up, it'll be a very drivable car. Nice and progressive.