What sort of connections should I use instead of the choc blocks or just get a longer length of cable
I used “wire gel crimp connectors” from ebay for connecting my flux gate compass, and while I had plenty of cabling supplied with the compass such that it was long enough to reach the course computer, if I had needed extra cable I would have been sure to use “tinned copper cabbling.” Ordinary copper wire can be a problem because the copper corrodes quite quickly in a salt laden atmosphere, and that leads to communication errors.
The gel connectors have gel within them and when you squeeze the connector some of the gel gets forced out, but the rest remains in place and protects the ends if the cable and ensures a goid electrical connection. They are readily available through ebay.
As for location of the fluxgate compass, on my B36(2002), I placed it on the transverse half height bulkhead that separates the starboard saloon settee from the chart desk, and placed it behind the back of the settee. Sometime months later, absent mindedly I placed something metalic inside one of the plastic cupholders in the shelf above and then wondered why the autopilot would steer anywhere but where I wanted it. Not for long though as I soon realised what I’d done. The next problem for my wheelpilot was the day when I forgot to release the helm brake . . . . . . .(sigh !!).