Hi, My son just purchased a house built in the mid 50's with Cloth wrapped BX cable. Under the cloth is something like rubber insulating the wires. It is very brittle and I want to replace it over time as we rewire or add circuits to home. Can we replace the 2 prong outlets with with 3 prong? (Is the BX housing ok as a ground for outlet grounding). Also since almost all wires are visible in basement with gentle loops from outlet to outlet, can we pull new wire through the existing BX?. My hope is to tie a nylon string to one of the wires and pull from the previous outlet box. mostly short runs, less that 8-10 feet. If that did not work, I was thinking of dropping one of the bx cables back through the floor , to create a straight cable to pull new wire, once i have new wire, pull in back into the outlet box. Am I being overly optimistic or is this possible. Figured I'd ask the experts before trying it. once I touch it, I'm committed to replacing it somehow, it's that brittle.