What trans you going with again?? I just found a local converter guy that is amazing, he is now my go to for all my Allison builds and he is building one for the Chevelle. We will start testing the new one for the Chevelle hopefully by next week. If all goes as planned, we may not be making the switch to a lock-up style trans at all and sticking with a 400 with his converter.
D&P Products out of Sacramento Ca 9169216600, His name is Matt Brooks.