it could also be the coil, i had the same problem but it only lasted about 5-7 hrs not 2-3 days, i changed the plugs and wires and distributor cap and it still wouldnt start when raining, but i changed the coil and it solved all my problems.
I had the same problem.It was coil on dist.I noticed under old coil the prongs were white from where it was arcking to dist.changed coil and it fired right up.these are bad for moisture building up inside coil.