The following assumes you are changing to an electronic regulator...The MCR1 top can be made to fit once you have removed the MCR2 coils etc. from their mounting plate...
You will then need to carefully file down the outside edge of the Tufnol plate that the coils were mounted on until the slightly smaller MCR1 top will fit over it and rest against the small 'stops' that are pressed into the base...Then you need to shorten/remake/replace the lid retaining clip for one that is shorter on each side...
I've bent them up in the past from a bit of stainless steel tig welding wire...They are the same as the MCR2 clip apart from the lengths on the side, which is pretty self explanatory once you take a look at it...Ian
