eBay list glass fuel filters with either 6mm or 8mm connection, had one fitted in the boot on tank outlet for years. Moved it to under bonnet just before the carburetors earlier this year, then had restarting problems when engine was hot, moved it back to the boot problem solved.
Moved it when fitting gates barricade fuel pipe, classic l should have left what was working alone, car Vitesse 2L.
Regards
Paul