What would cause a 1994 Saab 900 manual transmission not to shift into 2-4-reverse The linkage is adjusted to the end of the shaft what is the fix?

It >might< be a stretched clutch linkage cable, that is causing your clutch to not disengage even with the pedal pushed all the way down. My 95 had this condition, I don't know how many years Saab used a clutch cable that had no adjustments in it. If this is what it is, the trouble probably came on gradually as the clutch cable stretched with age. Normally with a worn clutch the 'contact point' gets higher and higher on pedal travel, but with a stretched cable it goes the other way and gets lower and lower. Solutions: Easiest temp (6 months maybe) fix: Cut a fender washer so there is a slot from it's outer edge to the center hole. Bend the washer in a semicircle...you should then be able to slip it over the clutch cable, between the clutch arm out of the transmission and the 'ball' at the end of the cable. Do it right and you will just have shortened the effective cable length by the thickness of the washer. I did this and got 6 months more life out of the cable before it finally streched more and snapped. If a dealer replaces the cable there is now an engineering bulletin out to put in TWO washers when installing the replacement cable, giving you that much more time for wear and tear before this happens again. OR, do some internet searches, I think someone makes an aftermarket cable for it that has adjustment capability. A year or two later SAAB solved this problem on subsequent models by using a hydraulic rather than mechanical cable linkage. If my guess is right, this has NOTHING to do with how your shift linkage is adjusted at all! Good luck, Paul