I've found it's not so much the panniers but the rack. You have to see how far back in relation to the bottom attachment screw that the pannier attaches to the rack.

I have one rack, a Burly, that my panniers hook in a good 3 or 4 inches behind where the rack bolts to the frame. Another rack I have a pannier only hooks in about half an inch back. And the third rack I own, the pannier actually hooks in forward of where it the rack bolts to the frame. Needless to day, the last rack lives on my bike with the longest chainstay.

Look for panniers that are adjustable forward and aft. I've never used one, but those briefcase panniers might work.