Ram Heater Core ?

I believe the heater core is going out on my '98 Ram. What looked like smoke (but smelt like coolant) was tricking out of my dash vents and there was a light film across my windshield (coming out of the defrost vents).

Unless someone tells me different, I am thinking it is definitely the heater core or an associated part. Has anyone experienced this in their Ram and if it is the core, can someone tell me how involved it is to replace. I am sure it is not as simple as our older Mopar cars.

Thanks in advance.