Hello everyone.
As most of you know, I did my engine swap many years ago now, and at that time I tried to install the M3 shift lever to get a bit shorter throw without a huge increase in effort.
(NOTE:
you can't have a shorter throw without an increase in effort)
At that time, I found that using the S52B32 with the original ti Getrag transmission and modified (shortened) arm and mount resulted in very little clearance between the shift arm and the balancer on the drive shaft. In a nut shell: the M3 shift lever cannot be used with this configuration.
What is needed, is a lever with the same (or less) distance 'under the ball' to clear the balancer. The photo below shows some common shift levers and their relative lengths:
And this photo shows another variety, with the stock ti shifter on top (with 120K so excuse the condition); Z3 1.9 in the middle (top shifter in the first photo) and the M3 on the bottom.
Between the two of them in the second photo, you can see what will work and what will not. The Z3 1.9 is what I have installed now, and I love it. Although it is slightly longer than the stock ti shifter 'below the ball' it
does fit. Clearance is very tight (3mm or so) in reverse, but otherwise 5mm or more, which I am comfortable with.
(NOTE:
if you have solid engine and transmission mounts you could get away with less clearance)
It has enough 'nochiness' to give positive feedback that it is in gear (which I appreciate), but it is not as difficult as the stock M Roadster shifter for example, where literally two hands are needed to get into reverse (for a woman I know who has owned an M Roaster since new). I was amazed the first time I saw her do this, but it is quite stiff going into reverse. That is the ZF transmission of course, so the Getrag may be easier? I don't know but someone else may have that experience to share.
Other options that will work in our case (swap guys with the ti tranny) are the Z4 2.5 shift lever, but that will be shorter than the Z3-1.9 and therefore more stiff/notchy. That will be 'softer' than the Z3-M shifter, but
will actually fit, unlike the Z3-M shifter which will not fit in our swap configuration due to the long length 'below the ball' as shown.
The final thing to consider when changing shift lever is the physical height of the shifter ball in the console once installed. As you can see, the height
ABOVE the ball indicates the position of the shifter in the console- how it relates to you, the driver. The Z3-1.9 shift ball location is ~1/2 inch low from stock ti location and the Z4-2.5 is another ~3/4 inch or so below that. I do not like the look of a 'sunken shift ball' and feel personally the Z3-1.9 is the best compromise on all fronts. In a track car with no center console, this is less of an issue and function is more important than appearance of course and in that case, I would probably go for the Z4-2.5 lever for the slightly shorter throw.
In conclusion, for those with a swapped ti that retains the Getrag transmission, in addition to the stock lever, you can use the Z3-1.9 lever (as I have used) or the Z4-2.5 lever, with the Z4-2.5 lever having the shortest throw and therefore highest effort. The shift ball will be lowest in the console as well with the Z4 lever and the Z3 lever drops the shift grip about 1/2 inch below stock ti location.
I received the lever and a full 'rebuild' kit from Ed (BimmerBum here) and everything went as smooth as silk as usual.
Short Shift option for Swap guys 
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