Hi Brian.
Adding fields to the scratchpad, is not a simple game, at least to my expirience.
You might need to overwrite/enhance several standard javascript functions, like:
pb_select_template
pb_clear_scratchpad
pb_qtemplate
pb_clear_pad_option
... and more.
That said, and I fully understand and agree to the business need of such an enhancement,
things like that have a huge impact, not only for the current product installation, but as well for each upcoming patch/release, whatever.
I'm not aware of any generic approach to achieve these kind of requirements.
Unfortunately, the SDM UI framework does not support an easy to implement capability when it comes to the scratchpad.
Nevertheless, I'm quite sure, it can be done.
Regards
...............Michael