Moving to the cup aux setup, new steering rack, rads etc etc is only bumping the cost up and up by silly amounts. Your looking at about £2k there is custom solutions.
And fitting another gearbox could be fine and dandy, but for the 5 units that might on the off chance get sold, what the point in trying? Anybody who's serious races, and racing cars already have solid gearbox's available. Road users need to have lots of money and want to spent it just to have some crazy car, at no point does value for money even enter the check list.
And i would build a turbo 'kit' as in i'd design and have the designs, but each and every time the components would be made to order and no stock held. There would be so little orders that it would be pointless to do otherwise. A solution that i would be happy with would be in the region of 10k as i hate doing things on the cheap or hanving any components ill fitting, designed or manufactured.
And the 197 i've not even bothered to look at yet, i will in time, but they are band new and nobody is going to delve right into them with work such as that. I would need to analyse the OE systems and see what is done where and why. Because of the variable vvt, a new camshaft profile and lots of time spent on the vvt advance maps would be needed.
Just think about how much money and time is required to do the solutions you thought of....its not fast nor easy, and i dont just sit round all day trying to think up answers then try them. I need to make money to fund other developments and ideas i have kicking around. Then you have to put a profit margin on everything you do and make money, otherwise its totally pointless.