Circuit Board for 6F Power Feed (With Upgrade Kit). This is the kit to upgrade your obsolete 6F power feed circuit board to accept the 8F circuit board. You will need to be able to unsolder/solder and might have to transfer and drill holes if your power feed has the box attached to the base of the mill. Comes with complete installation instructions. FOR THE AMERICAN MADE BRIDGEPORT MILL. SEE OUR STORE FOR OTHER QUALITY BRIDGEPORT PRODUCTS INCLUDING. REPAIR KITS, REPLACEMENT PULLEYS AND CLOCK SPRINGS. WE STOCK 95% OF ALL REPLACEMENT PARTS FOR THE SERIES I BRIDGEPORT. We guarantee the items are exactly as said in description. Appreciates your business very much. The free listing tool.