Abstract: A package embodying the invention includes a base plate for receiving an electronic device having input/output points to be connected to an external system. Side walls mounted on the base plate enclose the electronic device. Selected side walls have a plurality of hermetically sealed openings through which are passed conductive leads which extend from within the package to outside the package for connecting the electronic device to the external system. A ceramic insert is mounted on the inside of at least one of the side walls. The ceramic insert has a first set of holes (terminals) for the direct contacting and connection thereto of selected conductive leads. The ceramic insert also has a second set of terminals whose layout is customized for optimally connecting selected ones of the second set of terminals to selected input/output points of the electronic device. The ceramic insert also includes a custom designed conductive pattern interconnecting selected ones of the first and second set of terminals.