I've made a mini-board for illustration purposes; I'm not sure I understand your notation.
Chancellor: I don't understand. The one I have there is literally a Rook and a Knight.
General: You mean the axe, or the shield?
Lancer: Am I getting these suggestions right? The one I'm using may be a spear rather than a lance, but it does seem more suggestive of the job (at least, to me).
Nightrider: I had thought to use this Pegasus, but I wasn't sure it was appropriate. I'll go ahead, then.
Princess: HG seemed to be against this one in a. I'm checking that I read your coordinates right; if so, I'll go with column c.
If these are the ones you mean, I really prefer medieval siege engines over modern tanks.
I've made a mini-board for illustration purposes; I'm not sure I understand your notation.