If she agrees to let you apply in her name, usually the first few cards don't include a call to recon. If it does, most of us are in the situation where we start the call, when the agent asks, hand the phone to the spouse, spouse gives permission, you take it from there. A POA is overkill, and I am not sure a CS agent would have a methodology for that.

Start your wife with the Amex BCP, 6% off on groceries is pretty easy to understand (assuming your grocer takes Amex, and if she does the grocery shopping).

Great job on 47 years of marriage.