You can get polished stainless steel sheet metal "corner molding" in various lengths and widths on Ebay. It would be easy to make a simple angle bracket to attach to the firewall to make a shelf for mounting the reservoir- - - - -durable, attractive, and inexpensive.

Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!