Basically i removed the mach2 and removed the seal string. Clean both the evaporator head and cpu with amersil using cotton Qtips. I then checked the rear bracket and found the screw could be turned further, so i tightened the screws and checked the top bracket and the metal plate moved less. I took 2 1cm pieces of seal string and rolled nice and thin placed them either side of the metal plate , this stopped the metal plate moving, remember to press the seal string in place.
I then apllied a small amount of ceramique to the evaporator head until totally covered in a small layer of the evaporator head. I then used 2 rounds of seal string around the mach 2 head, i then screwed the bolts back on finger tight until i could not do them up any further.
Seal stringed the screws. Fired her up and WooHoo -112 idle -73 Evap under load -39 evap -66.
I am a very happy man, going to see what she can do now.