a basic cage will strengthen the shell massively, the diagonals can be designed as 'bolt ins' for track work. we have just had some scimitar cages designed and built by Performance and Protection in Skipton, and they have been designed so that they are modular. If someone just wants an MSA legal half cage (roll hoop and rear backstays) then they can and can add the front hoop and roof bars at a later stage (still fits with std interior) and then the door bars can be bolted in or taken out in about 4 mins per side.
If you speak to them, ask for Dan Evans, hes a top bloke and very helpful too. They have the coolest CNC tube bender you will ever see too
