Why changing a Gripen's radar affects the whole aircraft

Could a Gripen simply receive a French radar in place of its existing system?

The substitution would require substantial integration work because the radar interacts with communications, other electronics, and the aircraft's weight distribution.

A suggestion to substitute a French radar raises the problem of integrating equipment into an existing aircraft. The radar connects to communications and other electronic systems that must work together. Replacing it therefore requires changes beyond installing a different set. Weight and its distribution also have to be considered.