What board is in the hsw shocker? Is it a standard board (ie shocker 4x4 ds or ls) or does the hsw frame have it's own board? If its a standard board, I can help as I have one of each type (although the DS board one is in storage in York). Either way, the power wires goin onto the board are likely to be large square solder plates - for the standard boards they are on the top side (the side facing the main body when assembled with all the dip switches / pots). I can't remember the polarity so I wont take a guess on that, but if you look at the board very closely, if you are lucky then some of the info might be silk screened onto the board ie R1 for resistor 1 etc. In which case you might find theres a very litle V+ and 0V or similar by the solder plates you need.
Failing all this, if you've got a decent digital camera then take a photo of the top and bottom of the board and post them here.
Hope that helps somewhat,
Tom