I perhaps wasn't very clear on holding the transister.  The description I 
gave was with mounting holes to right and left.  If you do pull these, as 
you tighten down the mounting screws, make sure the sockets are centered 
in the heat sink.  I always check with an ohm meter from colector to 
chasie to make sure one of the mounting screws isn't shorting to the 
chasie.  Also, if you pull the chip, pay attention which end has the notch 
or indentation so you'll know which way to plug in the new one.
73
Butch
WA0VJR
Node 3148
Wallace, ks.