All of the C's that I have had, which is eight, have had the strap. The early B's had a bracket the bolted into the tool box/tank support instead of the strap. Later B's had the strap also. I have B's with both of which I have had seven. All of my B's and C's were owned by more than one owner before I bought them and could have had many modifications over the many years before I saw them.
The CA tanks had a indentation on the right side where the upper type starter rod was positioned.