MIMF

Some, not all guitars have a back strip installed.
Looking at the LMI back strips, I see that they are 1/8 thick.
Obviously this is too thick to inlay, so it must be glued in between the back plates.

This brings a few things into question.
Once installed, do you have to sand the back of the strip down to the same thickness as the plates, and then install the reinforcing strip inside?
1/8 is too thick for the back of an acoustic, correct?

Is all this correct, or is there a better way to do this?
Maybe sand it down before installation? That doesn't sound like a good idea.

I've installed it between the plates and then sanded. More recently, I've been joining the plates, thicknessing them, gluing on the cross grain reinforcement for the inside, then routing the slot for the backstrip (not all the way through the plate), installing the backstrip, and finally scraping it level. The marquetry in the backstrips worries me that it might be too fragile to handle the plate before the cross grain reinforcement with it just glued between although I've never broken one. I consider it a decoration with no structural contribution.