Volvo Repair: 1989 Volvo 240 DL Instrument Cluster and Alternator, volvo 240 dl, alternator problems

Question
Thanks for this forum; it's been very helpful.  As for myself, I don't know enough about cars so if I say anything that has already been posted or I ask a dumb question I apologize in advance. I'm always willing to learn.  So I decided that I could do the whole speedometer gear change myself and went happily to work when my new gear from IPD arrived.  When I put the cluster back in the dash after reassembly I noticed that out of the five plugs, there were two wires that I had not labeled.  The first I think goes to the speedometer (I don't have) and the second appears to have 4 prongs with one of them blocked (what are these for?). At any rate, I didn't plug them in and went about my merry way starting up my car and heading out.  That's when everything went wrong for me.  Now my speedo/odo doesn't work, nor do the heat gauge or gas gauge (both of which worked before the fix).  So I fished around behind the cluster and started making sure everything was tight.  During the process I accidentally plugged the tach? wire.  I think this was not a good idea.  Well, I stopped down the road to get gas and then my car wouldn't start at all.  Changed the battery and alternator, but the alternator is not charging the battery (when car is running the battery still reads about 12 volts).  What did I do wrong?  How can I prevent these mistakes in the future?  Do I need an entire new cluster?  Could the cluster malfunction have anything to do with the alternator problems?  Sorry about the long message but I am quite frustrated and would greatly appreciate any help.  Thanks

Answer
Dave, You must have put the white red wire in place of the yellow red in the right corner.  BAD news.  If you did that, then you blew the cluster. Those prongs are for cruise control.  I have spare clusters as well as doing custom work on them.  If you are interested, Let me know.  Roger