I have converted 96-97 gsxr 750 to efi, easy for that model as later 98-99 is efi and some parts are used
i think you need gen 2 busa throttlebodies to get better spacing match , there 75-90-75mm spacing make a crank trigger wheel, and fit a cam pin , both need accuracy in there timing 07 + gsxr 1000 or 08+ 750/600 wiring and ecu flash it as a busa to maximise options within the ecu
Check with Justin at Woolich Racing he has a number of New Gixxers that are able to be flash tuned without having to fart around with changing ECU's etc. www.woolichracing.com