Thanks both - it's a Tecnam P2002 Sierra, but not of the factory-manufactured/certified variety, so designated as a P2002-EA Sierra (Experimental). The certified (P2002-JF) and (UK LAA) homebuilt (P2002-EA) versions are structurally identical in this area.
The certified model has a Maintenance Manual which outlines of course the range values etc, as does the UK LAA TADS (type acceptance) document.
Neither of the above provide rigging instructions, the range/extension of the ailerons are far too great and I don't know how to fix that. Other builders don't seem to have had this problem. I'm a step away from thinking my kit - which was the first to be sold in the UK - has some incorrect part(s) supplied, or a manufacturing defect, but I want to try to cover all bases first before I go back to Tecnam in Italy. Tecnam UK has taken several forms since I first purchased the kit in 2005
Correct assembly has been verified, I just can't seem to adjust the pushrods and turnbuckles to sort this out! Thanks again