Phat one I have Turboed my 94 Elantra GLS and you don't have to swap the motor out. I just Turboed the 1.8l and never looked back.
If you wanna know whats up look at some of the earlier post under Forced Induction and see if I've answered any questions that you got and if not fell free to ask away and I'll help you out.
But to answer your question about will the 4G63T fit in your car yes it will but there is alot involed in swapping in that motor but if you have a donor car go for it.
<img src="http://www.speed-factor.com/turbo2_small.jpg" border=0>
AT 14psi HOLD ON TO YOUR SEAT, IT"S GONNA BE A WILD RIDE !!!!
For Pictures Visit http://www.speed-factor.com/hyundai4g63.html