The ECU grounds to the intake manifold at the back drivers side of the engine. Depending on year you will have 2-3 black ground wires with proper ring termionals grounding to the aluminum intake on the back drivers side of the engine. They should ground to the aluminum, not the steel (we have no idea why, but that's an age-old 6.5 thing).

When you turned the key back on after replacing the fuse does the wait-to-start light and check engine light turn on? If not, this is a sign of other issues.