CHI 4V heads question

This is a question for any owner that has installed the CHI 4V aluminum cylinder heads on a Cleveland in their pantera. 

 

During collision repairs I had a 404 ci stroker Cleveland built for 2511 and used the CHI 4V heads. 

 

I did not change the GTS exhaust pipes/mufflers nor the GTS headers supplied by Dennis.

 

But something has changed and the exhaust pipe will no longer correctly mate with the header flanges. With the mufflers as close to the body as possible, there is a gap at the top of the header flanges of about 3 sixteenths of an inch. Even removing the ZF side mounts and letting the transaxle rest on the rear crossmember, there is still a header flange gap. 

 

I’m thinking the exhaust ports on these heads may have a raised header bolt pattern and this is the source of the misalignment.

 

Has anyone else found similar misalignment problems after installing these heads?

Thanks,

 

Larry