Bruce Lee:
https://en.wikipedia.org/wiki/Bruce_Lee
my sense of it is that your 'spiritual guide' is much like Bruce Lee, and has his appearance in your
dreams. the "some kind of mission" you've been involved with is likely to be the reasons you've
incarnated into this physical life. in a sense, you ARE the Bruce Lee character; that is your spiritual
component which cohabits with your other aspects. the scene where Bruce came into the vehicle
is where the spirit took charge of the activities... the "slamming" and queasy feeling may relate
to displacing whatever 'natural spirit' may have been in place.
i have a rather uneasy feeling about your situation, and a concern that you not allow your Lee
spirit to dominate (through ego induced motivations) over the other aspects of yourself. taking
your vehicle up that mountain is the "dream mission", where you're achieving heights of physical
expression unreached prior to now (hence no guard rails, since it is 'uncharted territory'). i urge
you to seek harmony between mind/body/soul/heart and whatever other aspects of self are
present, since all are to benefit and none are designed to suffer through your accomplishments