These are the common options. Every unit had a battery except for the 500 w/ opt 2. I never understood why IFR sold batteries with opt 2 (high stability TCXO) for the battery would time out in 10 minutes and the osc would not be stable until approximately 15 minutes. Usually, after 3 cycles of the battery, it is time to get it plugged back in. The std TCXO's (most common) are generally on time at startup or at least in the ballpark.
The software is basically like this: "7.1-XX" or 6.1-XX" etc...The "XX" would reference: