BMW Repair: 1983 533i electrical issue, clutch slave cylinder, clutch master cylinder

Question
While driving up a very steep hill our 1983 533i suddenly just died.  When trying to start it again it would start right up - as long as the key was in START position.  As soon as key returned to RUN position the engine would stall.  My significant other, really a very experienced mechanic, but not BMWs, checked out several ideas as to the problem. We at first concluded the fuel pump must've gone out then he discovered that there was no current to fuse #1 except during the key being in START position.  We replaced the fuel pump relay - this did not solve the problem.  We've checked all the fuses, they are all good. This isn't the same problem as the car starts runs then suddenly stalls and won't start again for several hours problem.  We've been through that quite awhile back.  We've been having an issue with the clutch slave cylinder not operating properly probably leaking brake fluid, we've also had a few other minor issues since we've bought the car about a year ago.  We just recently had it smogged and it passed. So.....Seeing my significant other so stumped is really unsettling for me.  Please advise of any knowledge you may have of this kind of an issue.  Thank you Very Much.

Answer
Checking the body ground for a good clean connection and the braided ground for any corrosion.The fuel system gets it ground through the body,if this wire is green in color or broken you will have a starting problem.The leaking of brake fluid could be the clutch master cylinder or the the slave cylinder or it could be a leak in the cylinders to the brakes as well.When fluid gets low over 1/2 in the reservoir clutch operation will be affected.