I've been pretty liberal with the contents and it doesn't quite work yet but.
2 Toyota TS040 (2014)s, because there's no hypercars.
5 Revenga (Rebellion R13)s, 2 Rebellion, 1 Alpine, 2 in Glickenhaus livery.
2 Vendetta (Ginetta) V60
1 ByColin (ByKolles).
17 Oreca 07
1 Ligier JS P217
You can just about find enough unique real liveries for this.
Debating which Ferrari 488 to actually use but 5 of the acrl ones right now.
2 works Corvette C8R
3 works Ford GTE (but I can't find liveries that even work with the one I've got)
2 works BMW M8 GTE
2 works Aston Martin Vantage GTE 2018
4 works Porche 911 RSR 2018
4 Porsche 911 RSR 2017
2 Corvette C7R
3 Aston Martin Vantage 2017
Using the older cars for Am keeps them behind. It's not a "real" grid but there's some distinct classes and enough cars to fill them.
Cutting it down to 24 for short circuits was tricky, I need to investigate because the one race I tried a car didn't ever move off the grid but it's only an Oreca 07 so I can't quite work out why yet.