This site ...
Tesla VIN decoder. ... has this for the 8th digit ...
1 = Single motor
2 = Twin motors
3 = Single Performance motor
4 = Twin Performance motor
5 = P2 Dual motor (usually MS or MX)
6 = P2 Tri-motor (MS or MX)
A = Single motor - standard (usually M3)
B = Dual motor - standard (usually M3)
C = Base Motor, Tier 2 Battery or Dual Performance motor (M3)
D = Single motor, std winding (usually MY)
E = Dual motor except M3, std winding (usually MY)
F = Performance, std winding (usually MY)
G = Base Motor, Tier 4 Battery
J = Single motor, hairpin winding
K = Dual motor, hairpin winding
L = Performance, hairpin winding
N = Base Motor, Tier 7 battery
P = Performance Motor, Tier 7 battery
S = 3D7 Motor
... but no 'R'. Need to hunt around a bit more to see what we can find.