Anybody share my gripe about the LX470 Drivers Seat lumbar support?

My 99 LX470 Drivers Seat really could use more (positive / convex)
lumbar support. It just doesn't adjust to a very positive/convex
degree, and my average-build lower back would appreciate more support.

By comparison, the seats in our other vehicles (96 GMC truck, 04
Sienna) DO have good lumbar support.

I believe that Lexus may have designed this seat for the "95th
percentile" LX470 buyer - a person who fits the typical affluent
middle-aged American shape profile, meaning with extra girth around
the midsection. The seat might feel good to that person, but not me.

I'm tempted to take the seat apart and add some material to the lumbar
support area myself. Anyone done this with this seat?

Many thanks in advance for suggestions / info.

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