So I did the M52 swap, and used the shift lever and selecting rod from the 328 with the getrag tranny.
The shift lever and selecting rod are a little shorter than the 318's units which is needed to make sure that the pivot point is properly placed for the shifter arm.
However, there's a curve or offset-ness to the 328 shift lever which causes the pivot point to be to the right a bit (off center) looking from inside the car. The ti shifter arm didn't seem to fit with this setup as it hit the front of the shifter surround trying to get into gears 1,3,5,etc.
The 328 shifter arm is a little better but still has the same problem of hitting the shifter surround and also won't go into reverse gear at all. The shifter assembly also rubs the driveshaft when trying to go into 2nd gear too.
Anyone have any suggestions of how to get over this clearance problem and get better shifting out of it?