Just a heads up ref. no. plates
As we can probably all remember cars in the UK up to about 1979 when new had aluminium no. plates with raised plastic letters, then for about 2 or 3 years one piece pressed aluminium ones and then from about 1982/3 the type still used today, plastic laminate.
The ones on my car being a 1976 were the raised plastic letter type and the rear one was the original from new still with the supplying garage name on it (Anca Garage, Worthing) and front although original style had been replaced sometime back in the day although slightly different in design. The original plan was to restore these but on investigation the alloy was too badly corroded especially on the front one so I needed to have a rethink. Ebay turned up plastic ones and the boy racer german font ones in pressed alloy, no good for what I wanted so I found a company called 'Framptons'
http://www.pl8s.co.uk/index.html
Their raised riveted type were just what are needed for SI & SII cars (and older alfas etc.)
I ordered a pair over the phone, they asked for a scan of the car log book and passport
They arrived and look great, the alloy edges needed a bit of finishing off especially the square rear plate to remove burrs and pressing marks with wet & dry paper, steel wool & then some wet scotch but now look fab.
These come undrilled and the rear plate was slightly (1/4") taller than the original one so you need to be careful and accurate when drilling as the bottom hole positions are set really because of the boot lid handle. These are a lot more expensive than the plastic ones at £65 the pair but to me look a lot better and worth the extra.
its one of those things that is impossible to remove without damaging it
all I have managed to locate in the last year or so are 3 pistons/rings/pins in .40mm oversize, not much good unless I can find a 4th one!! 
