hi all. i have a 1989 90 with a the original td engine in. I want to fit a tdi but im not sure which. Ive been looking through loads of posts and cant really find what im looking for. I was planning on a 300 tdi as they seem to be more readily available but do i need to modify the chassis to fit the 300? So can anyone point me in the direction of the threads i know ive seen somewhere. Cheers