The manual is notoriously bad for information on this part, rather than document it all here, I'll direct you to the 310build blog post, which covers everything pretty much perfectly, and all the wires end up the same length at the end of it all!
I have however recorded a timelapse of constructing the second lighting rig, this may be easier for others to follow (I'll swap the clear for orange pre IVA just in case), seen below. Here are some photos of the parts I used too
- IVA - Grommets, Heat Shrinks, no exposed wires!
- When gluing the IVA trim, be very careful not to get it on the pod, I did, tried to remove it with glue remover, and ruined the pod. I ended up ordering another from the Caterham Parts website!
- It is worth getting the extra heat shrinks and doing it properly, it makes the rest much easier.
- Use better grommets, don't bother with Caterham supplied ones
- I used a plastic dash tool to push grommets in and out
- Make sure the bracket fits over the wish bone mounts before starting!
- For IVA I think you have to put the orange indicator covering back on, I'll do that once the build is done.