Clarity?
It sounds to me as if you are seeking to seeking to remove the entire head, leaving just the crossmembers, frame, and base. If so, you simply take out the screws that hold the lower focus rack (on the lower part of the rack below the lens). These are attached to a bracket that connects to the bottom crossmember. Then remove the big bolt that is seen from the back. It is in the bracket that is attached to the top crossmember.
I have attached the exploded diagram of the enlarger, as well as the head/stage alignment instructions that you will need when you reassemble. If you are disassembling the head as well to strip or paint, this is slightly more daunting, but can be done.