I think it would be cheaper to find a 2ltr Megan bottom end than to change the crankshaft/pistons in you current lump, the 2ltr bottom end and the F7P head fit striaght together, they use the same gasket face. A fully worked F7P head/manifolds, 32mm inlet valves, Piper 270 cams for a Willy (higher lift), supersprint manifold and possibly a reworked TB should make something quite interesting, this is my project for the winter.
Also been talking to Ben about a longer term project to build a 1800 lump able to rev to 10,000rpm, would need, billet crank, forged rods, forged pistons, nitrided crank, MASSIVE porting, 32mm or bigger inlets, 45mm TBs at least, eletirc oil/water/power steering pumps, possible duplex cam chain. Gonna be expensive and time consuming, but in a fullystripped out valver, roll caged and well setup susspension should make an interesting track car.
Cheers, Simon