Large Scale Central

Lionel RailSound triggering

Before I tear apart my old Lionel 442 Atlantic and GP Diesel I was wondering if anyone here has identified how to trigger the various RailSounds the locomotives have built in via DCC or R/C? I would like to have some info before I start to root around.

These two were some of the first large scale engines I bought so I have kept them packed away in their original boxes.

thanks in advance.