How do I add and delete units from a nation?

[Edi]

Originally Posted by Endoperez

I seem to remember that in some cases, there are three types of units available from certain levels of PD. The mod commands don't handle that, and they aren't listed in the manual. I'm not sure when I read this.

Some nations do indeed have three tyupes of units in PD, usually low quality stuff. Those seem to be hardcoded. It's possible to mod two types of units into PD, but not three.

I'm not sure if #clearrec will also clear PD for a nation. It might be worth a try.