There are 40 events - 30 Trophy + 10 TT - shared across ten tracks, with each track hosting three Trophy events (one a Cup) and a TT...the track sequence running Bugatti > Laguna Seca > Mount Panorama > Spa > Silverstone > Monza > Nürburgring > Red Bull > Catalunya > Le Mans. (I was a bit distracted but seem to recall you need to complete all three Trophy events on a track before the next one will open up)
PR86.3 from the LTS will get past 75%, but the Catalunya and Le Mans Cup races need PR87.2 and PR89 respectively.
Progress Rewards split:
25% - 5GC and M$7,000
50% - 10GC and M$14,000
75% - 15GC and M$21,000
100% - 20GC and M$30,000
(For the record that last Le Mans Cup race is 5 laps and winning pays M$108,700 but only 6,900 Fame)