Rewards: 49 Gold, R$49,000
Location: SEASON 2
Unlocks from: Own Nissan Z
Maximum Required PR: 39.8

There are 51 events - 47 Trophy + 4 TT – each car has a specific TT and 2-event showcase, plus there's an 'open' TT (which is bug-ridden##) in Tier 18.  Fully upgraded the 300ZX can't reach 75% on its own, whilst fully upgraded the 370Z just reaches it on its own. Only the Z can be upgraded enough to open the last 3 cup races (PR 32.7/36.1/39.8) to complete the series.

Progress Rewards split:
25% - 6GC and R$6,000      [PR 9 using 300ZX , PR 12.8 otherwise]
50% - 10GC and R$10,000   [PR 15.5 using 300ZX or 370Z, PR 19.7 for Z]
75% - 13GC and R$13,000   [PR 29.1]
100% - 20GC and R$20,000  ## unable to claim because of bug 

The Nissan Z upgrades cost:

(As usual courtesy of Paulo at FB RR3 Trackside)