RE: OS 7D carb
The 7D carb came on the .61 FSR motors and the .61VF (rear exhaust). It had a removable sleeve inside the throttle barrel on the .61 that was removed when it was used on the larger .91 or 1.08 motors. The 7D was an excellent carb.
Oh, and it had nothing to do with an old beat up Taurus plane