Rewards: 79 Gold, R$79,000
Location: SEASON 1
Unlocks from: Own Any Car In This Series
Maximum Required PR: 96.4

There are 51 events - 48 Trophy + 3 TT - with each car having a specific 2-event Showcase + TT.  Only the Bugatti can be upgraded enough to open the last couple of cup races, but sufficiently upgraded any one car on its own can reach 75%.

Gold progress rewards are:
25%  -  10GC
50%  -  15GC  [PR ~78.2 if only using Porsche or Lambo, a bit more if using only Bugatti]
75%  -  21GC  [PR 85.8]
100% -  33GC