I have installed both the B&M and the SVSI shifters, but have removed them for what I think is a better arrangement for the track. I found that both of these shifters were fine for street use, but on the track, during high reving conditions, they are a different story. The SVSI gates are so close together and the springs are so soft that it is very easy to accidentally shift from 3 to 2 when you want 3 to 4. This can be disasterous to the engine if you don't catch it in time. The B&M is also the same problem with the soft springs. On another note, the stops that are supplied with these shifters serve no purpose, since according to the people at Tremec, stops are already built into the trany. If you get these shifter stops set too close, you will not get into gear properly, and you will damage the gears when under high load. If you decide to use the B&M or the SVSI, your best bet is to remove the shifter stops completely.
I found that the best arrangement for me, for street and especially track, is the stock shifter modified with a stronger spring in the left side gate only, and no change to the right side gate. This makes it much harder to accidentally pull a 3 to 2 shift while the engine is highly reved. Bob Woodhouse sells these shifters modified by K&P Engineering. I have many track miles on this design and like it better than anything I have used. You will not likely run into this 3 to 2 problem unless you drag race or road race, but if you do, you will likely over-rev the engine and do some damage. I also replaced the stock isolated stud, with the SVSI 3.5 in. solid stud and replaced the shift knob with a shorter one. Here's a picture of the modification and the stud.
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