No Ascona came to the UK, think that the ascona b and c came to the UK as vauxhall cavaliers mk1 and mk2. Not sure the models spec matched. Wasn't one a GM world car?
The only Opel sold in the UK was manta.
EDIT Wrong, GM had some odd ideas with vauxhall and Opel tillearly 80s
The ascona never came to the UK. (EDIT: It did, I was wrong)
The most famous manta in rallying was the Andrews Heat for Hire liveried Brooks rally car.