Gary,
Our P40, "Journey", is same vintage (1982) and deck stepped. I've had the mast off twice in the twenty years we have owned it. On our vessel, the wires are continuous through the deck, down through the stainless steel compression post, where they exit in the bilge, and then go aft to a big terminal block under the main salon settee behind the bulkhead. When we unstep the mast we just take everything loose at the terminal block with an attached tag line when the bundle is pulled out of the compression post on deck.
Jeff
SV Journey
Ventura, CA