As far as i know the 2LT head will fit on top of a 2L block - you will need to go for the 2LT configuration rather than 2LTE as the 2LTE has a vastly different fuel pump, Crank Position Sensor, vacuum pipe configuration etc etc.
Things to think of.
Lowering the compression ratio, just fitting the head will not do this, you need a spacer gasket - they are available.
You need the Head, Turbo, Exhaust Manifold, Inlet manifold top end, preferably the fuel pump, all vacuum pipes, Air filter housing (turbo pressure sensor fits into it), Front exhaust pipe, coolant pipes to the turbo plus T pieces, Block T piece for the oil feed and returns to the turbo.
Plus you may not know what condition the bottom end is so you should really check over and change BEB and Mains if in doubt plus rings, pistons etc if you want to make sure you really have everything covered.
This is eminiently possible though, as is fitting a 2LT head to a 3L engine - it will fit that engine too.
Only the early 2L engines had rockers, later ones had the same config as the 2LT and 2LTE with the direct activation of the rockers. pretty sure the bolt pattern is the same though however if it isn't then that would be the killer.
However with a head gasket spacer and exhaust manifold (it should bolt straight up to the 2L head) and all the stuff like the pipes etc then it should be possible to turbo he motor with the existing head on it. Keep the boost around 7 or 8 psi and you should be OK with engine reliability as well although the 2LT and 2LTE can be pushed up to 11 psi with ease or though you will suffer with engine longevity.