Only a few minutes more
I'd just pull the cover and tab the dowel pin. It only takes a few minutes more, and when the cover is off, you can loc-tite and torque the other bolts inside the gear case.
The bolts get loose and fall into the gears just like the KDP does, so it is worth the slight extra time.
Every KDP fix I've done has had loose bolts, and two of the pins were out so far that the jig wouldn't have worked anyway.
It just takes a few extra minutes.
JMHO Greg L. The Noise Nazi