It depends on what engine it has. I am not sure what was fuel injected and what was carbed that year, or maybe everything was fuel injected.
There was a big change in 87 or 88, that's when they changed the gauges in the cluster, and the resistance in all the sending units is backwards and a different value compared to the earlier units.
Somewhere around 86 they changed everything to the large hole type tanks, so that is a difference.
During all this, the diesels were their own units. They have no in tank fuel pump, but they have a extra fitting for a return line.
The carbed 460's had a in tank electric pump, and a return line.
All the fuel injected sending units had a in tank pump and a return line, some were low pressure pumps like the 460 carbed, and the later ones were high pressure in tank pumps.
All the early units with carbed gas engines(except the 460's) had a sending unit with no pump and no extra return line fitting.
And going along with all this, the wiring plugs can be different, and the type of fuel lines they used can be different, with different types of fittings on the sending unit.