Excluding 4 lug cars, the EEKs had two front rotor setups. The common size (10.25") was used with rear drums and solid rear discs. However, on the cars with vented rear discs, there was a larger front rotor (11.00"). You'll gain more from swapping to the larger front rotor than adding discs to the back. And you will need to run your 15" wheels, 14s won't clear the larger setup.
Upgrading to the larger front disc is simply a matter of swapping the caliper adapter bracket and getting the larger rotor. The caliper may not change. For example, I looked up 1992 and 1995 LeBarons in the factory parts catalog. The caliper was the same for both setups in 1995 but was different between 10.25" and 11" rotors in 1992.
For the rear, the same car that provides the caliper adapter bracket for the front can provide these. Looks like the spindle is the same disc or drum.
Upgrading to the larger front disc is simply a matter of swapping the caliper adapter bracket and getting the larger rotor. The caliper may not change. For example, I looked up 1992 and 1995 LeBarons in the factory parts catalog. The caliper was the same for both setups in 1995 but was different between 10.25" and 11" rotors in 1992.
For the rear, the same car that provides the caliper adapter bracket for the front can provide these. Looks like the spindle is the same disc or drum.