Graham, There are a few 4 3/4" Tachs out there. You should check out egauges (_http://egauges.com/vdo_main.asp_ (http://egauges.com/vdo_main.asp) ). Ned Madsen MCCA President - Wichita, KS 1966 Corsa 140/4 speed 1965 500 Sedan 95/PG www.KansasCorvairs.org