I altered the standard ormerod 2 extruder body so that it could be fitted with a pneumatic fitting to hold the bowden tube .
The extruder is made to be tapped for a 6mm thread which I found to be a nice neat fitting. The fitting I found on Ebay quite cheaply
Item Number 271290823788

I also beefed up the extruder on the inside of the curve between
where the filament enters the extruder and leaves the pneumatic fitting
, It always looked to me that the filament would soon wear through the
extruder body on the standard part