I’m not sure I can be of any more help - but hopefully someone with more knowledge will chip in…
But more generally:
It hadn’t occurred to me that the horizontal base could fitted in that way, but I can foresee a couple of possible problems there…
I’d looked long and hard at the MFK700, but the general advice on the FOG was that it perhaps wasn’t the best choice for my present situation and needs. However, I’ve since found that a friend actually had one and has lent it to me to have a look at (haven’t used it, but I’m already thinking of future projects that might justify it later on!).
Fitting the horizontal base vertically, as it were, does a ready-made straight-edged base that could be run up against a rail or straight edge as a guide, but I’m figuring that the height adjustment won’t work with the base locked in in that way.
Also, if it’s the “1.5 degree” base, I imagine the face of the base will not be at a right angle to he axis of the motor and cutter - which may be good or bad depending on the task at hand.
Also some improvisation would be needed for dust collection.
EDIT:
"but I’m figuring that the height adjustment won’t work with the base locked in in that way."
I was wrong on that point: I misunderstood the way the base was locked on, the height adjustment still functions. But I think the other caveats apply.