the question is how much power, cant say what'll work till you know what is expected. or if there is a power output in mind can suggest combonations of bits.
the ABF is quite a tough enigne, leave the head std for turbo valve seat area is usefull to help keep the valves cool and abf cams are quite well suited to turbo, F all overlap but lots of lift. the cranckshaft is pitty tough and supriseingly well balanced out the factory.
you can just stack headgakets and it'll take a fair bit of stick but stackign gaskets removes the squicsh zone and premotes detonation so you'll have to run 97 juice and keep the boost pressures quite low for the compression, use notched 8 valve pistons the boost pressure can rise in relation to the cr.
the NA pistons can make good power `if you look after them but get it wrong and there will be an epic fail, feeding the engine boost is placeing a big ask on them and it used up the safty margin if it starts detonating the heat and pressure will smash them.
the other issue is the bearing shells ther really want changing for s2 items if you want it to last