Done 250k miles in my +8 1980. Clutch slave cylinder is one of the few components that only failed once. Diffs, gearboxes, steering boxes, wiper motors, alternators ..... and most other parts failed far more often in 38 years of ownership

Must be the Auto Gods.
I have done that type of mileage and, from memory, I have been between 5 on a 1984, 1990 and a 2002. until I discovered the cure, One time was at a major Eastern US event where many here were there. On the other hand, aside from my first LT77 I have never had an alternator, a differential (Salisbury or BTR), steering rack, a wiper motor or an alternator fail me though i have upgraded as I deemed wise. My comments do not come from my car alone, I am sent 5-7 new problems a day for the last 25 years.
I will trade you my old components for your old clutch salve. (smile)
Keep up your great usage!!