Kurt.mills98

Hi there I new to this sort of stuff but anyway I have a ke70 project car it has a 4a cross member in it ready for a 4a to be dropped in, but I'm having troubles with the gear box I assume I need a t series gearbox but does that mean I need to change the gearbox cross members from k40-t50 and if so how hard is that to do. And also with the diff do i need a ae71 manual tail shaft and will that fit a ke70 diff?