Race prep for modern cars

[drmotorsport]

I'm in the middle of prepping a 2008 Fiesta and disappointed with the level of rust i'm finding (yes it's a cheap Ford so what else should I expect!). So anyway with half an eye on planning ahead to the next gen car, I was thinking of a nice shiny Audi TT mk2 with better galvanised shell etc. Turns out that the shell is a mixture of aluminium and steel with a variety of welding, bonding etc, which raises the question - how the hell do you weld a MSA spec CDS or T45 roll cage into an 'exotic' shell like this?

[HustleRussell]

What does the Blue Book say? Presumably it is permissible to bolt the cage in. There will be a minimum standard for spreader plates, bolt sizes etc.

Also, what do the technical regs for the championship say?

[drmotorsport]

HustleRussell said:

What does the Blue Book say? Presumably it is permissible to bolt the cage in. There will be a minimum standard for spreader plates, bolt sizes etc.

Also, what do the technical regs for the championship say?

It's more of a theoretical question of the practicality of installing a steel cage into a car with differing construction materials. I did think bolt in cage could work (although looks amateurish), but then you still need the reinforcing plates welded to the shell... Maybe i need to get Googling on how DTM, TCR teams build these things.