[CAD_CAM_EDM_DRO] Machining width

I have a case where I need to use a Taig to machine curved (bowed)
fiberglass to a new, specific thickness which varies down its length. I
can stand the part up on edge and probably use a diamond sanding drum
for removing material from one side to achieve the desired thickness. I
cannot start from a fiberglass block or anything like that it needs to
be remachining these pieces already formed in a curve (the glass fibers
need to run the length of the piece continuously).

How can I regulate the thickness? My first thought is to cut a holder
in the exact curvature of the original piece, mount the fiberglass in it
and run the cutter in a fixed toolpath. However, the part's original
curvature may be slightly inconsistent and if it does not exactly fit
the holder's curve then the thickness will be wrong. The fiberglass is
too thick to force into a holder.

I've had a number of ideas, even touch sensors to sense the thickness,
but nothing's really jumping out at me here.
One of the better ideas is to machine a somewhat flexible strip that
goes on the back of the fiberglass whose thickness increases as the
fiberglass's specified thickness decreases, so when they're paired
together the total thickness is constant and I can hard-attach a guild
roller to the cutting head itself (not the table) at a fixed distance
from the cutter and feed it through.

It's an idea but there's a lot of funk to that, the line between the
guide roller and the cutter's center *must* be perpendicular to the
fiberglass's curve. So there is thought of mouting only one end of the
fiberglass to the Taig table, using a mount with a bearing that can
support rotation, and use the Taig table to steer that end of the
fiberglass back and forth to steer it as it feeds. It's a thought anyways.

Any ideas?

Danny