I don't believe that GM calls for the new bolts on 99's. If you
happen to be able to get them, by all means install them, but
it's not absolutely necessary. Even when GM first released
the new style gasket and the accompanying bulletin, the bolts
were unavailable. GM stated to simply clean the old bolts
and use loctite (which is what you always were supposed to
do). So until the bolts became available, this was the method
used. This went on for a period of months before the new bolts
The new bolts simply come with the loctite pre-applied and
no longer use a washer under the head, but have a pre-applied
lubricant/sealer under the head of the bolt.
It's basically intended to idiot-proof the process. If you were/are
already cleaning and applying loctite to your bolts, that would
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