On the matter of getting the angles one wants:
        Most accounts of shoot board construction seem to focus on getting
the stop, whether straight or miter, installed at the desired angle to the
line of the already-existing bed for the plane.  Not having the benefit of
experience, I approached this task in reverse, with good results.  Some
time back I made a simple bench hook, with the stop on the far side ending
about 1 1/2" from the left edge of the horizontal body.  To facilitate
lining up the saw for cutting, I placed a framing square against the stop
and drew several parallel lines on the body perpendicular to the stop.
I.e., the stop was the register for marking lines from front to back, at 90
deg. to the stop.
        That procedure led me to the following steps for the shoot board:
I installed the stop on a 1/2"-thick board, roughly perpendicular to the
direction I expected to slide the plane, and placed a(n accurate) square
against the stop, already fixed.  I was pretty sure that the line marked
along the blade of the square would be 90 deg. to the stop.  I jointed the
edge of the board to that line, then affixed it atop a wider board, thus
forming the bed for sliding the plane.
        I haven't made the desired miter shoot board yet, but when I do I
expect to again do things backwards:  Fix the stops at (roughly) 45 deg. to
the direction of the grain, so that they form a right angle, and then mark
45 deg. out from each stop and mark the board along that line.  I will then
plane the edge of the board down to the line, and afix that board atop
another wider one to form the bed.
        Have I committed some sin for which I will pay pennance in the
course of some future project?
                Tom Holloway