I would think as long as you route wire away from exhaust it doesn't matter where you take it through, I also notice your choke is on left whereas mine in on right nearest driver, it also doesn't go through bulkhead above cross member but underneath, the bracket on carb is different to enable this, but my car has no heater valve just a brass tap on the head which has to be operated under the bonnet. But I have found loads of things changed on early minis and it's difficult to know what's right or wrong. My fuel gauge didn't work and have traced to a stuck sender unit but pre 64 are different to later as no voltage regulator on speedo and gauge is different. Managed to free it so saves the hassle of trying to find one.
I would also advise you clean all terminals on electrical connections and check for brittle insulation as they only cause problems later.
You are on what I think the hardest part of restoration so good luck and take your time.
I am now on the frustrating bit of ironing out minor problems on a car that hadn't been used for 30 years, then have a little bodywork touching up to do where I had a couple of little accidents but in no rush.
If you ever need any help or info let me know.
In fact thinking about it that large hole in bulkhead behind heater is where my choke cable goes,
I also think two spare wires where they are maybe the horn but easy to test as one will be permanent live and other earth when horn push pressed in
Edited by Daz1968, 02 August 2015 - 12:55 PM.