[LATECH]

It has dura spark I or duraspark II
both use a pickup coil in the distributor. IIRC the brank sensor setup started in 81
Duraspark II cap and rotor/wires are arranged differently

The distributor cap and rotor are of a special two-level design made to accommodate the additional advance capability of the EEC system. Both the rotor, Fig. 3, and cap have upper and lower electrode levels. Distribution of secondary voltage from two separate levels allows for up to 30 degrees of distributor advance.
IIRC duraspark I is a standard cap,rotor,wires
Probably the only difference

 

[LATECH]

There is also an early /late production change to the distributors/cap/rotor
early were held on with clips,late production had the cap base screwed on.
If you change the cap/rotor/wires to one or the other, you need the whole enchilada

 

[LATECH]

80 and up use a crankshaft sensor
79 back not
of course ford does a lot of mid year crazy stuff. late 79 may have gotten a crank sensor, or, a choice of the 2 different dizzys

 

[LATECH]

I disagree I had 2 customers with 79 with crank sensors.

OK
It has ben a while since I have seen a 79 versailles
Alldata is likely not 100 percent on this one .Typical
I do remember working on those back in the day
The ones with the sensors in the back are a real joy to change

 

[LATECH]

Too Bad OP did not post wether or not it has a ignition box