to swap a 4g63 here is your shopping list:
1 running 4g63 n/a auto eclipse/talon/laser
93-96 (I believe) elantra mounts
axels of some kind...I don't know what an auto tranny requires, use the search function and look for the people who have done the swap with the 4g63auto tranny(although I believe you can use your stock ones with the dsm auto tranny).
Tips:
1.Read my articles in the newbie forum, there great cause you'll start off knowing kinda what your talking about.
2.Either search or use the newbie forum. You need to know what questions to ask, before you ask one that is so broad.
3.do not use the stock auto tranny that comes with your csm...it is weak.
4.you need to grab the engine,tranny,downpipe,wires(uncut),vac lines,ecu etc...out of the donor car.
5.grab the top and rear mount from an elantra.
6.ask questions when you get stuck.(were not complete assholes

)