[TR] Battery Drain

[TRDOCTOR at aol.com (TRDOCTOR at aol.com)]

My '72 GT6 seems to have a slow drain on the battery.  When hooking up  the 
battery there is a small spark.  When using a test lamp that is  grounded, 
it lights up slightly and then goes out.  Have checked with all  of the 
fusible circuits and it doesn't show up.  Could it be a bad diode in  the 
alternator?
Suggestions?
 
TIA
Sam Clark
Green Country Triumphs