ANSWER: Both of these are 743.1. As explained to me, if there is a small ridge around the insulator just above the upper wire ridge, then it is a 743.1. The absence of a ridge indicates a 743.2. Thanks Debbie!! I guess I now have an extra 743.1.

I have two CD 743.x pieces and I need some help trying to identofy the proper CD. The one on the left is beefer with a more rounded dome and is slightly taller. It also has a higher wire groove and the wire groove appears a little wider. The left one measures 2 7/8 across the base and is about 3 3/4 high. The one on the right measures 2 7/8 across the base and is about 3 5/8 high. I guess the right one is a CD 743.2 by the measurements (it matches the book), but the left one does not match to either the .1 or the .3. Can anyone help? Thanks.