I just recently bought one of these for my '59 Imperial. It fits just under
the brake fluid canister. I bought it at Auto Supply Club Whse. which are
scattered throughout Southern California. The part # is SLS28, and is
manufactured by STI, and here's the best part, it only costs $4.19! It may
need an adapter to fit in to your '59, but these are readily available.
Bill '59 Crown