Hi,

In answer to getting the mainshaft 13mm bolts off you'll need a couple of
GOOD quality long handled 13mm wrenchs. Using one open ended and the other
closed you can do it.  They are torqued down well.  A 6" one won't cut it,
8" or more is best (she said),  Nuts are crimped prior to assembly, look for
the marks on two faces.  Don't substitute cheapo nuts for replacement.  I
reused mine but will get new ASAP, and I should've Locktite'd them!!!!
Dropping the wrong end of that shaft into the dirt could probably push the
entire trans and motor out the rear, or at least pole vault you a ways.   Tim