The bridge rectifier can also be mounted on the heatsink to.
For this reason i mount them off the board and wire to them.

The capacitor bank on the input side can be changed to a single large cap if you have one suitable.

The 5 watt resistors will run rather hot under high load and need to be mounted with air flow around them.

I have often soldered them direct to the pin of the transistors with the other leg connected together and wired back to the board.

When purchasing the 2N3055 transistors ask for them to be all the same batch number as this will help eliminate internal differences.

The pot values shown might need to be changed to allow adjustment over the desired voltage range and current limiting range. A test with the output leads shorted together will soon show max current settable range.

A suitable transformer for the amps required will be needed. It is a simple circuit with a hand full of components.

The only need for a pcb is for the LM723 and the 3 small resistors and 2 caps. The rest is mounted to the heatsink or front panel and wire connected.

Maximum input voltage is 40 Volts.

See LM723 data sheet for more details.