I had a 1990 T Spark in red and had it re-sprayed (due to fading) as well as the lusso alloys done. Had it lowered too with a K & N air filter. I bought it with 80,000 miles and sold it with 125,000. It went as strong as ever and didn't use hardly any oil. In the 4 years I had it, the only things that had to be replaced were the tyres and parts of the exhaust and a steering rack gaitor. Other than that it was just new oil + filter every 6k.
I now have the delightful 24v 164 Cloverleaf which I bought with 95,000 miles. I've had it 2 years and have (again) had it painted due to the red fade. It looks like a new car though. I am working on getting the alloys refurbished. Its now covered 118,000 miles and really doesn't use any oil at all. Its had a cam belt and tensioner change about 10,000 miles ago. The car still feels fresh and punchy and regularly upsets BMW and Subaru Impreza drivers who have spent £££££'s on their boring yuppie-mobiles! After paying a fraction of this for an individual performance car 2 years ago, it makes me smile.
From time to time, I get the jitters about the mileage. Some people seem to think that once a car gets over 100,000 miles they fall to bits, but in most cases the major work has been done and its like a new lease of life! The same case with my 75 T Spark.
I say, keep the oil changed regularly and get any bits that obviously need doing ASAP, otherwise it can start a chain reaction of faults!
164s especially are very few and far between (especially nice ones), so look after 'em!!