Should help, but somewhere on the trans is a tag with more info. If no one chimes in before I get home I'll look at my old trans on the floor and tell you where the tag is.
Basically any trans from a GT that is 98 or 99 will work directly. Can't be from a GTP (has different gear ratio). If you go with a 00-02 GT trans then you will have to change a fluid line on the trans as the 98-99 has different size fittings on the case.