[DeTomaso] Header gasket to exhaust port match?

[Ken Green]

It appears that my exhaust ports are maybe 0.2 smaller width and height than the gaskets I've found.  My heads were probably ported for a restrictor plate motor, and the gaskets are sized for larger ports.  The smaller ports appear to be a good match for my engine parameters.  Should the gaskets openings being a bit large matter much?
 
Thanks,
 
Ken