Thanks for the location on the #'s. Mine appear to be the d2's. Found out today that up to .600 lift (with matching springs) can be used in the original heads. Machine shop is suggesting I go with rocker shaft studs instead of the bolts. I would really like to find an older intake to use to help keep the "old" feel to the car, but haven't had much luck locating one that will flow good enough. Again, thanks for the advice-in a couple of weeks it will be "Off to the Races!!!"