Here is some pictures for Ian.
I'am trying to find a good pictures of the cage. Base cage is Fia styled 6 point cage which is also welded to windshiel frame and targa posts. There is also additional tubes which go from front hoop to front shock towers and from towers to front axles front attachment points.
The way i have done it is not the best one. You really should add connection tube because the shock tower is quite flexy where i have welded the front tube. I will change the original shock tower support to tube one so that will solve the flexing problem. I will also add tubes to rear attacment points of front axle. Rear has normal rear support tubes which goes behind targa posts and other tubes which goes to rear shock towers (our rules are quite funny so you should maybe use only 2 rear support tubes which goes straight to shock towers). Then there is tube from shock tower to other and also 2 tubes to gearbox support. I will add lower tubes from main cage to rear suspension frame.
Its hard to explain but please ask.

First picture is the old one and you can only see the "official" rear support tubes. It would be wise to make those longer and weld them in the place of the extra ones that you can see in last picture.

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