I chose to install these painted lower cabinets 3/4" proud of the surrounding drywall/lathplaster opening. this complicated things because the casement molding that surrounds the opening has to butt up against the face frame assy. of the cabinetry. You want to avoid having the spring of the interior curve of your casement on a lower plane than the cabinet's frame, which is exactly what I set myself up for here. The result is we'll have to fur out the casing a bit in order to make it look OK with the cabinet.
Here's what i'm driving at below. you see how i've lifted the casement molding off the wall and we'll have to lift it even further to get it looking alright. Tim and John both had mentioned just trimming the inside curve a little bit via table saw and this will help push the spring of the curve out further.
I might have some little white shims under the cabinet that could also give the appearance of plinth blocks to allay any worries held by serendipitous, classically trained, neurotic guests, worrying about what i'd done...
drawbore pegs driven home for that breadboard end. very satisfying indeed.
also, here you can see how the sapele is not full thickness. I figured it would be a waste and I have since attached some transverse oak battens with expansion slots for the skrews. this should help keep the board from cupping too much (i hope)