Quick reply from Carey. A flat 6 cannot be stuffed into a speedster or ConvD. Completely different chassis and rear suspension from the Super Coupe. So if you want to ride with the big dogs you need a Super Coupe. I know that in order to stuff a flat 6 into an IM, Henry had to do significant modifications to the speedster pushing the engine forward in the chassis. This helped with handing but created drastic CV joint angles resulting in the car to eat through CV boots. BTW this also happened to my IM which had a very tall VW/Audi 2.0 engine resulting in extreme CV joint angles. The Type 1, Type 4 and suby cars have very neutral CV joint angles and do not eat CV boots.
Joel you might want to ask Carey if your car will require exaggerated CV joint angles. Lots of money to change these boots if you don't do it yourself.
Might have to look into getting more performance out of the 2.5 Suby. I absolutely will not turbo charge. I'm so tired of turbo lag.