This is a little confusing . The connections to the selenium rectifier do not match the markings on it . There are 4 tabs 2 on the top row 2 on the bottom row . The AC is connected to 1 tab on the top row and 1 tab on the bottom row same with the DC. The marks on the rectifier case has both AC on the top row and both DC on bottom row .
The insulated wires are from the transformer .
The insulated wires are from the transformer .