Interesting. I've got one of those knocking about somewhere too - been separated from the car for at least 28 years...... never knew what it was. My alternate sealing arrangement means it'll stay separate too.
Nick Jones Somerset UK
Vitesse Mk 1.5 Convertible EFI, Survivor of RBRR 2008, HCR & 10CR 2009, HCR 2010, 10CR2011, HCR 2012, 10CR2013, 10CR2015, HCR 2016 & HCR 2017. GT6 Mk3 Roto - project in progress Spitfire MKIV son's project now on the road as a daily driver 2.5 PI Saloon now EFI (PIe?), Engine rebuilt and running sweet. Diff howling...... Survivor of HCR 2013 & 2014 Gone to live in Swansea