http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=2DSC00022.JPG sorry about the large s??t picture!

45 Dellorto`s by the way?

Try this site http://www.racecar.co.uk/dellorto/ they are the UK Dell'orto importers or give them a ring in the morning they are normally pretty helpful.
Cheers, Pewe

Here see if you can find it on there. Looks like the blank for the pump jet weight.

Think you will find it's the place you fit adaptors for carb balancing.
Regards
Dave

I have the speedpro series book on how to tune dellorto`s and it doesnt say anything about them. They go to a point at the end of the screws but not as fine as the idle mixture adjusting screws are and they are in towers whith springs too?

There are the Idle bypass screws for balancing up the flow rates at Idle.

ATB Dan.