067 133 432 A - adjusting screw - £9,87
Easy job to replace, unwind the old one and wind in the new one about the same, then adjust it till your idle is at about 900

Once I finished the 2.0 conversion mine unwound itself every 2 days cos of the sheer powerÂÂÂ

Edit: You live anywhere near Bracknell? I could get my CO meter & timing light on it for you, it would be nice to get a look at a running MK1 to help us when we get round to fitting the engine to our cabby!