Thanks all for the replies (Ian, L, Geoff and Dave).
L: The only problem with those larger bulk head type arrangements is the depth of them. There is only around 15mm max of room between the back of the mirror cell and the mirror itself, and I currently dont have the mirror all the way down (the collimation screws are not fully tightened). I could use the bulkhead and bent the pings slightly I guess. It seems as though RCA might be the go, and I can use the RCA arragement when I get my DSC's going too. Thanks for your efforts though.
Geoff: do you have any images of your RCA setup? I grabbed some of
these today from our local electronics store (ugh) because its all they had (and I think I was lucky to get them!). I might try mounting one of these on the back and see how that goes. If not I can try something else.
Dave: interesting setup! Where do you power the cigarette style attachment from? I'm using a 9v battery at the moment, but planning on upgrading that to a gelcell or similar soonish.
Thanks again everyone.