As far as the motor not being "perfectly verticle",...that's something that isn't always a true statement!! The older "8" series boats (ie, 882, 884, and 896's) all had their motors mounted a little left of verticle,....only a few degrees, but deffinetely noticable if you sttod behind the boat and looked at it. This was done intentionally to counter act the normal torque of the motor and it helped to eliminate the chine walking of those hulls. When I first noticed it on my 896 I freaked out,...thinking maybe Ray Charles or Stevie Wonder did my rigging, but after I was told why,...it made sense and that boat did and still performs like a dream......never had chine walking problems. BTW, the motors ARE verticle on the 9 series hulls. I don't know that much about your 170DC hull, but if I remember right, my 190DC's all had Verticle mounted motors too,.....but I really doubt your hull is warped!!
It's probably just a case of motor torque and one of the "personalities" of that boat,....i doubt it's a problem!!
Good luck this fall....
Mac