So had a few random 3 hrs sessions over the last few days so a quick summation...

Dion tube:

Brake line attached & built up the ears & stuff. Can I just thank Andrew Bissell & his fantastic Blogg! I have to say without this I would have ground to a halt really really quickly. The photo's with the bolts for the ears & brakes is invaluable. I have used his blogg for lots of things but this bit saved the day. 

http://caterhamsevenbuild.blogspot.co.uk/2014/01/build-day-11-rear-wheels-left.html

One thing I hadn't picked up on, the nut that holds on the 3 way brake adapter to the Dion tube stud is not metric.... after a bit of searching I found a suitable lock nut with a white insert... Didn't do too much damage when I was attempting to put on a metric nut...

I had purchased a brake line bending tool... waste of time when you already have a fixing on the end of the tube as you have no room to use it...used a large socket to bend it around like everyone else seems to!

Next stage the manual says insert the tube from the right hand side of the car as if its really important. I was a bit worried about this as I had no room on the right hand side. Inserted it from the left with no issues at all... who knows...

A frame,

after fannying about got this loosely connected.

Shock absorbers 

Disconnected A frame.... feeling well pleased with myself that I'd put on my roll bar & then suddenly remembered I hadn't torqued the bolts up... well remembered me!... mucked about for a good 10 minutes trying to find an Allen key that fitted with no joy, I then finally peered up the tube & noticed I hadn't put a bolt in... for gods sake... this is the trouble with doing short sessions... anyway... bolt inserted, & torqued up... job done.

I can now see why you are warned not to strip the lower bolts of the shocks. After mucking about for a while I got the bolts in & managed not to strip them. Then re connected the A frame with no issues.

Radius arms

Checked with Derek & these go in the bottom hole he also advised that the pressing should go next to the caliper... I obviously ignored this snippet of info & found out why you do this when I tried to assemble the brakes...Had to drill a hole through the bottom hole as there was no corresponding hole in the steel behind it.

A frame

Forgot to mention that before I did the radius arms I put the washers on the end of the A frame. By some miracle I ended up with 4 on the LH side & 3 on the right hand side (which is what it says in the manual!) & the ends of the Dion tube were identical each side when measured to the chassis... wonders will never cease.

I was getting a bit tired now & started losing the plot a bit...

Started assembling the ears & brakes & inserting the half shaft... Struggled a bit & called a halt when Derek pointed out I'd not put on my rear brake disc...

update: also noticed from photos on Jerrys Blogg (https://jigthecat.tumblr.com/)  that I left off the two spacers from the brake caliper... oops... but better to find out now anyway! I probably would have noticed when the disc didn't fit in the gap...

So I sort of have a rear suspension installed just need to get the brake bit sorted & make a start on the rear ARB...

One thing I did find out.. the hub nuts are different sizes! The one with the LH thread (nearside) has a 41mm nut which I had previous bought a socket for.. the RH  (RH thread) side has a 41.5mm nut... Derek has said he will send me one which is very nice of him!