"But my understanding is that MOST ZF6s with lighter single mass flywheels rattle like hell."
I have the F 13# and it does rattle a lot at low RPM in 1st and 2nd when you are lugging the motor.
At a stop as well but only when the clutch is not depressed in.
With my ceramic clutch the combo is great IMO and worth the PITA noise.
I kept my DM so I could always convert back if I wanted to.
Along with my secret supplier ECM chip I get some extra spank from the LT-5.
All else is stock on my Z.
I got my set up from Carolina Clutch but this was long b4 Jerry had his offerings = no doubt I would go with Jerry if I were to do it today.
Someday I may go with headers and an exhaust system for more bang but I figure I am on borrowed time with my stock injectors and vacuum system.
So far the "corn squeeze" has not got to my injectors - I do fire up the motor every 30 days all through the winter(s) and use seafoam as well.
62K now and I put about 500 miles on a season. I am a go fast boat guy first and a fair weather Sunday ZR-1 owner 2nd.
THE FOX RIVER IN MY BACK YARD
READY TO GO AT AN INSTANT