Have you seen this: http://roadstershop.com/galleries/nre-pantera/
Might give you some ideas. Also, keep in mind, the transaxle you have is set-up with something like a 25%/75% front-to-rear torque split. Even though it's the same transaxle, the Lamborghini version has less torque directed towards the front than the Audi R8 version does. That being said, the R8 still has a significant rearward bias because they want it to feel like a RWD car. Of course this bias only applies on dry roads!
Getting back to the shifter topic, Fran at Superlite Cars is making shifters for Graziano transaxles because OEM Audi/Lamborghini shifters are so hard to find. He's the first to admit the OEM Audi/Lamborghini shifter has a nicer feel.