And thanks for the advice regarding shimming the rear engine mount, i'm glad to hear its a common problem regarding the frame cracking there.
I have just been in the garage making my new powervalve cable, really happy with it! So i now have the powervalves rotating how i want them. I've made a video which i will try and upload here.

The cable i made is at the bottom and the one at the top is the longer of the 2 kips cables.
Video isn't playing ball at the moment but i will sort it.
Maccas