I had my seats out in the week and looking at the frame, I suppose it might be possible to cut a section & reweld out to make the base smaller.
You may run into difficulties with the mechanism though...
I would be wary of lowering the seat though as you need to think of other things like where the airbag is going to deploy and if you need to rejig the seatbelt pretensioners.
If its mainly the visibility onto the instrument binnacle, why don't you remove the top cover and reangle the instruments with some packing under the bottom, so you can see them?