[British-cars] MGA seat update?

[vince at capaccio.name]

I have a 57 MGA that I am restoring as a driver and was considering updating
the seats to something with more side support and more confortable.
I have welded in 3 point seat belt brackets from CSR and whatever update is
done seatbelts are a must.
Have you seen or done something like this. What seats did you use or did you
modify the pading under the covers?

Vince