what have you done with this, ditched it and blanked the holes or what?!

Yep, blocked the holes with ali panels under the cover.

Second that!
Bin it and blank the holes - my blanks aren't quite as professional as Hellfires though

I am going to use washers and bolt them on.

I left the valve still connected and just removed the hose that attaches to the airbox. It must help the engine a little as it draws in quite a bit of air as the engine is running.