Adcom GFA-565's or Eagle 400 mono blocks

I'm not familiar with the Adcoms, but have a lot of experience with the Eagles - though not the 400's. I'll be interested to hear if anyone has actually compared the 565 and the 400.

I have an Eagle 2C', a 2C, and 2 Eagle 4's. You rarely see Eagle 400s used, so I'm not sure if you have a line on a pair or if you plan to have Russ Sherwood build you a pair out of a couple of Eagle 2's. If that latter wile it will run into some cash - the latest versions of Eagles (with Russ's updates) are fantastic.

What speakers will they drive?

Unsound they will be driving a set of B&W 808speakers

These are a set of Eagle 2c's that have been converted to the 400 mono blocks

not sure what you did pay or will need to pay for them, but assuming it's in the ballpark of what I've seen them listed for lately, doubt you'll find something better for less than twice the price.