Time for an update!
As I'm planning to fit a larger engine into my SS1 it seems sensible to make as much space as possible in the engine bay. The driver’s side of said engine bay is very crowded as the battery, brake servo/master cylinder & carb/inlet manifold are all situated on this side. Of the three essential items mentioned above the battery is, by far, the easiest to move. The SS1 boot has a false floor hiding a deep well which presumably is used to carry all the spares/tools you'll need on any sort of journey - it's also known as the "drug compartment"! It's pretty useful really & is an ideal place to re-site the battery. So I spent all day Saturday moving the battery from under the bonnet to the boot. Not a particularly difficult job - more fiddly & time consuming than anything else.
On with the pics:
I used a junction box in the engine bay to connect the original battery positive cable to the new length of cable which will run to the back of the car.
I ran the new cable under the fuse box & through the big bulkhead grommet that the main loom passes through.
Here's the new cable passing through the bulkhead grommet (you'll have to turn the picture through 90 degrees), I've run it down the bulkhead to the right of the pedals & then along the base of the bulkhead under the pedals & then along the base of the transmission tunnel. I've secured it with plastic p-clips along its whole length.
I didn't order enough cable so I've had to join two lengths together - here's the brass connector prior to the next length of cable being fastened to it - the connector comes with a length of heat shrink which I haven't shown.
This shot hopefully shows the route of the cable through the car - it also shows the p-clips I used to fasten the cable down.
The rear bulkhead caused me a problem as it was too thick for any of the grommets I had, so I made a little metal plate (thin enough to take the grommet) to pass the cable through. I then ran the cable down the left hand tank strap, protected it with some heater hose & secured it to the strap with a couple of cable ties. 
I secured it to the chassis to the rear of the diff with a p-clip & then passed it through a hole I drilled in the boot liner. Again I didn't have a suitable grommet so used a length of heater hose to protect the cable (I'm not sure how legal this is so I may have to change it later) I've fitted cable ties either side of the boot liner to stop the cable, & hose, pulling through the hole.
I also made a strengthening plate to fit under the boot liner & bolted it up to the car using the bolts I've used to secure the battery tray inside the boot (it's the original Reliant battery tray - as mounted in the engine bay - but with the legs cut off).
The earth cable was next on the agenda - pretty easy to do & wonder of wonders I found a grommet that I could use - I've bolted it to the drivers side rear chassis member after I'd cleaned all the underseal/rust/crap off.
Here it is all finished – I don’t have a picture of it but I’ve since made a false floor for the boot out of wood which hides the battery.
A couple of weeks ago I was hoping to get the Zetec installed - which would obviously have been a big step forward - unfortunatelt the friend who was due to help me had car problems & couldn't make it over to my house. I didn't fancy attempting the engine swap on my own so it was put on hold until he'd got hs car sorted out & I had more time. The tentative plan now is to attempt the swap on the 29th of this month. I'll be taking pics if it goes ahead so, hopefully, I'll have another update soon 🙂
