as long as your car is an original manual equipped, you won't have to modify the trans tunnel. if your doing an auto to 5 speed conversion, that's a whole different story.
on that trans x member, where the tubes are on either end, you'll see how those tubes are tac welded onto the trans x member. grind off those little tac welds, which will allow the x member tubes to slide forward and back. that's all you'll have to modify. as long as you have the 3550 bell, everything else should bolt right up.