The bolt pattern for a 1976 Ford LTD depends on the wheel size and whether it's a 6-cylinder or V8. There wasn't a single bolt pattern across the board. You'll need to check the wheels themselves (the number of lug nuts and their spacing) or consult your owner's manual to be certain.
However, the most common bolt patterns for a 1976 Ford LTD were likely 5x4.5" (5 lug nuts on a 4.5-inch diameter circle) or 5x4.75".
