I did this event last year in a couple of races. I'm pretty sure there was no noise testing. But email Patrick Quinnou who runs the show and he will tell you. Great guy and very helpful. I think he also has other races there that may be more appropriate - a GT and sports car race.
Here is the English bit of his recent email:
We are happy to announce a new series
for pre 63 Sportscars and pre 66 Gts. Two events this year
Grand Prix de l'Age d'Or, June 19,20 & 21, Dijon Prenois
Grand Prix Historique de Provence, October 30,31& November 1, Paul Ricard circuit
For more informations visit our website
http://www.gpao.fr/en/series/sc---gt-challenge.html
Patrick Quiniou
GPAO
8, av. de Condé - F77500 Chelles
+33 1 70 00 04 04
+33 6 07 98 21 86
www.gpao.fr
g.p.a.o@orange.fr