Maybe consider a HT ingot 1 shade lighter than the target shade, and stain the ging as needed, and just cut back and layer the facial Inc 1/3rd (keeping the ling intact for the strength as the Drs probably looking for) for the desired stain effect/Inc effect as your looking for. As long as you maintain around ~6-7ths (confirm the thickness in the wax up),you won't show a prep line or lower the HT value when your working with a nice background like that. Using a V (opal/MT) ingot, you probably wouldn't be able to get the across the board chroma coming through mesially-distally, having to use much stain to make up the difference=s muddy looking.
This is the one I'm currently working on, not quite the nice prep shades as you have