dmrtn9203

Can anybody tell me what size the tubing is at the flange from the converter to mid pipe on a 97 ls400? I feel like an idiot asking a question like this, but I have no way to get under the car and check right now, and need to try to get parts ordered this weekend. My exhaust is leaking bad at the flange, and I'm planning on doing a custom cat-back 2.25" exhaust and want to replace the leaky flange with a v-band if possible. Thank you!