The old type seals are OKish for N/A aplications, but they get blown loose easily in turbo engine. Ford changed the type to the newer one piece type a LONG time ago but the two piece type still lives in other spare part shops.

Sorry, I don't have any gathered information of my car in the internet, but I'll be happy to answer if you have any questions. Also the picture is years old. I'm also building a non original S1 with the same management that I have found excellent. Rough spec:

DIY Megasquirt engine management with MS'n'EDIS code update.
DIY mapped fuelling and ignition
DIY ported efi cylinder head
Mondeo EDIS wasted-spark ignition, with multispark option.
DIY built wideband controller
S1 bottom end
mk5 Escort flywheel, inlet, throttle setup and head
GRS S1 intercooler with twin kenlowes
Magnex exhaust
Kent CVH 35 cam
Motocraft 071 plugs
DIY ecu controlled boost control
DIY hybrid gearbox
2.5bar MAP
Bosch greens
Knock sensing
All sort of gadgets...