Some of them are totally encased in the heatshrink, others have the triac hanging out to be bolted down for heat-sinking. I have new ones in both configurations in my parts boxes. Most of the Legacy ones went with the exposed triac, probably because they failed so often without heatsinking.
As for having to open it up, I just match the spacing of the wires to the standard pinout, I've never seen one that has a different layout.
