The 9 pin MOLEX connector on the back of HR2510's Lincoln's and Hr2600's are not very convienent,
and the addition of external jacks is fairly easy to do.

Using 3.5mm jacks make the most sense, and they will fit nicely between the heat sink fins and the existing
Molex connector.

Installing a 'single close circuit jack' will allow the external speaker to automatically turn off the internal speaker,
and you will not need the MOLEX internal Speaker jumper plug (Standard on HR and Lincoln Radios).

The diagram shows how to connect the External Speaker and a PA Speraker jack to the existing circuit.

The wiring from the circuit board to the MOLEX jack does not need to be disturbed,
all connections can be made on the bottom of the main circuit board.
I move the White wire from the speaker to the center pin of the new EXT. SPK. jack
and then run a wire from there to the + side of the speaker.

For the PA Speaker jack, You could use a non-switched jack, just connect the board
wire and the MOLEX ( 7) wire to the same terminal on the jack. (Switching function is not needed).

If you have no use for the PA Jack or need to add a CW jack, you would connect it the
same as the PA jack. just use MOLEX wire 9.(Switching function is not needed).