You can replace both inside and outside micro switches......it is not to hard, once you get the door opened up..... I am fighting a "wont drop" issue without much luck so far.... I have replaced the outside handle micro switch, Done the cable tie trick, and replaced the regulator.... With a cheap one.... Which I will likely suffer for.....
I'm having the same problem as you with a "won't drop" enough issue, it drops a little but not enough as it should. The electronics in these cars have a lot to be desired.
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1999 Boxster base w/sport package Ocean Blue Metallic/Savanna Beige