You have probably seen my posts about how important heat shielding is for a F600. Well, insufficient shielding melted/distintegrated the RR puck in Clint's F600 during the Runoffs race preventing Clint from challenging Brian Novak for the lead. I am sure that the many attempts at meeting the varying sound requirements during the week took all their time and attention, thus there was insufficient time and attention for proper heat shielding of the new exhaust arrangement even though there was some distance between the exhaust and the RR puck.
If in doubt, HEAT SHIELD EVERYTHING!!! It is far, far better to err on the side of too much shielding. Too little will hurt you while too much won't hurt you.
HTH,
Jim