3.6 heads on 3.0 case?
 

I have a 3.6 (964) race motor but I need to use a 3.0 case to make the car qualify for the type of events I want to enter. Rather than selling the motor and building up a 3.0 motor from scratch I want to try and rob the 964 motor of everything I can and try to use a 3.0 case. I realise the head stud spacing is different but I wondered if anyone has tried to change the stud mounting on a 3.0 case to fit 3.6 heads

Medication.
 

I reckon if you're even thinking about it you need to change your medication.

Could never be worth it.

We have changed the stud spacing on a 3.0 RSR case to fit 3.0 SC heads. It is a simple proposition and there is no reason that you can't change the spacing to fit 3.6 heads on a 3.0 case.
We have also fitted 3.6 liter cylinders to a 3.0 case. We have installed 3.6 cranks in a 3.0 case.
So I guess the answer to your question is that you can make a 3.6 with 3.6 head based on a 3.0 case.