TTI Header Fitment Issues

How do you shim the 73 and up mount?
My distributor is already real close to the firewall.

That's the thing, they fit on the 73's and the K-member measurement is correct as I said in my other post there is enough space to create some wiggle room so this problem dosent exsist even if the car isint perfect. Heck the way it is now you have to raise the engine a 1/2" to 5/8" to get them to fit as it is which is out of spec