If you need to retain a TCT to manage resources that you cannot define using RDO, you should eventually remove from your TCT source all the definitions that have been successfully migrated to the CSD file, or that are now being created by autoinstall. This saves time on table assemblies.
After reducing the TCT source to a bare minimum, reassemble it to ensure that you have not made any mistakes.
You continue to suffix the TCT, and code TCT=xx, where xx is the table name suffix, as a system initialization parameter. If you have VTAM resources and DFHTCT macros, code ACCMETH=(VTAM,NONVTAM) in the TCT.