1423 left was tested and given the okay on the 3rd June 1974.
Best
On 27 Aug 2015, at 00:43, jfranmac@gmail.com [newmellotrongroup] <newmellotrongroup@yahoogroups.com> wrote:
The serial number on this M400 appears to be #1423. Anyone care to guess the year it was made? He lowered the price a little.