Well, the 1998 block will only work after a certain date since "early" 1998 blocks don't have the revised mounting points for the MTX-75. However, if it is and you are comfortable living with a possible oiling issue in certain situations (hard right hand turns), it's definitely a cheap way to more power IF you do all the work yourself. It would require all new gaskets (timing cover, valve cover, heads, etc.) and new head studs. Everything else comes from the 2.5L donor. If the 2.5L is low mileage, you could retain the timing wear components (timing chains & guides). Not doing ANYTHING other than tuning (no head work, etc.), I would guess 180-185fwhp. I wouldn't bother doing this on a non-SVT because the gains would be less and not worth the effort in my eyes.
