The picture below shows the Focus exhaust manifold attached to a Sylva silencer as requested. 

You may notice the engine now has a fan belt! As the engine is from a Focus, the alternator and tensioner are from a 1250 Fiesta, it's little wonder that neither a Focus or Fiesta belt fits! The crank pulley on the Focus is larger diameter than the Fiesta. I could have changed the pulley but that means redoing the cam timing; the Zetec SE has a keyless crank. So I investigated a different belt. The standard 1250 Fiesta belt is 1181 long. Looking at the Gates catalogue, the most suitable belt would seem to be 6PK1195, 14mm longer. This belt is fitted to BMW 750i and a Fiat Punto 1.9D! It also fits my Riot perfectly. 

I'm now working on the fuel tank and pump. Just waiting for some 8mm high pressure in-tank hose to be delivered. This is important as standard fuel hose is designed to convey fuel but not to be fully immersed in it! May have the tank in this weekend!