The sloppyness of a tailshifter has to do with the linkage between the shifter, and the transmission in a 914. The gearbox itself isn't a problem. I wouldn't say that mine shifts as tightly as a 915 in a Carrera, but it's a good shifting unit.
Quaiffe makes a LSD for a 901. There's a recent thread about it.
http://www.germanlook.com/Forums/showthread.php?t=9429 $1600, or something like that.
