It's basically the same trans. There were valve body/channel plate upgrades/changes over the years. But 99 GP to 01 Bonnie. Yeah Almost every part is interchangeable. You'll have an internal selector switch (Bonnie) vs an external, but if you follow my how to add an external pnp to a trans, it's one nut and two bolts plus lining the part up. Poof you have external.