Hello Mark
I belong to a small group of Gash people researching their ancestry in Lincolnshire. You ought to contact Amanda Lee who holds our database.
This is her website and there's an email address there - she's quite busy though so might not answer straight away.
http://homepage.ntlworld.com/geomand/index.html
You would need to give her the information you have already to help her find your connection.

Friendly tip though - don't use capital letters - in emails it is classed as "shouting".

Good luck.

Hilary