the wiring diagram follows what you need to do. the difference with your PCB is that the three holes in the top middle are for the LEVEL control. On each side of those three holes you will see two holes -- the + and - connections from the power jack are marked. the small holes next to them are for the ground wires from both of the audio jacks (as shown in the wiring diagram)
What he said. To add to that, make sure you orient the potentiometer correctly. It should be mounted on the side opposite the components, Lug 1 goes into the square pad. It should extend past the edge of the PCB, not sit underneath.
I'll post a pic as soon as I'm back at my workbench.
1N4148 & 1N914 are interchangeable. Their electrical specs are identical. HOWEVER...
R9, R10, D1, D2 & Q2 DO NOTHING. You can install them or leave them out, the Triangulum will work the same either way. Look at the Integral, it has the same "do nothing" circuit. Now check out the Isosceles, it's the same circuit, except with a boost switch. Note the absence of the "do nothing" circuit at the input.