Saab: 1991 Saab dying after a few miles, control circuitry, few more miles

Question
My 91 Saab had the alternator and harmonic balancer replaced a couple of weeks ago. A little less than a week ago after driving it in the morning for about an hour it would die. After waiting for about 20 to 30 minutes it would start back up and drive for a few more miles (sometimes just a few hundred yards) I left it and came back the next morning and it did the same thing. I changed the fuel filter and it ran for two days and died once, when it died I tried it 3 times and ran with no problems for 1 more day. That next day it died three times, each time it took just a little bit longer to start. But not to risk being stranded Im leaving it sitting overnight. Could I have a "sock" problem or does it look like another problem. PLEASE HELP  I need this car to get back and forth for the time being......................

Answer
Eric:
 Did this problem appear ONLY after the alternator replacement was done? If so, there is a likely connection, however remote. If you think that it is just a coincidence, then I would investigate the fuel pump or fuel pump circuitry as a likely culprit. One way to start this investigation is to temporarily hotwire the fuel pump as follows:

a. remove fuses 27 and  30

b. make a jumper connection between the OUTER (fenderwell) side of fuse #30 to the INNER (engine) side of fuse #27

   The pump should now be heard to run continuously.

  This bypasses the control circuitry and if tried right after the car stops running (if you dare run it again)can help verify/isolate the problem.
  A place to start
             Hope this helps
                          Jerry