I've just had several brainwaves...

1) Could you use the 87mm pistons from the F20C in the K20A2?
2) Could you use the 87mm pistons and the Cylinder head on the K20A3?
3) Could you use the Cams from the F20C in the K20A2 head (it uses the same valve springs...
4) intake manifold, header etc etc...