It is't the 3L that adds the work/expense.. it is the MTX swap which requires a new subframe.
Either way, standar 2.5, SVT 2.5 or 3L, you are looking at the same OBD-I/OBD-II conversion, wiring harness, etc.
Only differences would be pricing (cheaper for the 3L) and availability (easier to find a 3L)
Ray