if you remove the chrome in the corners THEN it will be asy to hard solder (850+ Celsius with decent silver solder Ag as high as possible = lower solder temp but strong enrough)
you need to see what happens to the "thickness" in the corners where the chrome was OFF..as new Chrome will leave a slope/step.
I would try to leave as much as possible Chrome on the visible side, only remove it on the back side and then hard solder it. I assume a thin layer of chrome then would do, def on the visible side.
I DO NOT KNOW the min thickness required to really have the chrome stick - needs a chat with your chrome folks...you probably need to "swivel" it down a bit.
One more issue: if you bend the chrome plated U shape rails the chrome will crack..so Guess is better cutting real edges then hard solder them....this is all EXPERIMENTAL..you need to run some tests..
Matthias