I wouldn't use wire nuts, esp that many in such a space because they like to unscrew themselves etc, and besides the whole thing will kind of look terrible when you're finished. I'd cut the old ones one by one and solder the old amphenol socket terminal (for the pump, blower, etc) directly to the new wiring. Be sure to use the right size female disconnect terminals on the other ends on these too. Most should be of the 'blue' variety (size wise, what you would normally purchase from home depot or radio shack). Another alternative is to cut the wires from each amp plug (these are the pump/blower plug etc), about 1.5" and attach new wire, (I'd still solder them), then slide over heat shrink tubing over each connector and shrink them up.
Or, you could just go purchase new amp socket connectors... radio shack, rs electronics, etc, and work from there. Assuming the model number you gave me was correct, this diagram should correspond to your unit, use with caution:
http://alliedinnovations.com/pdf/W2209c.PDF
This is a long job to rewire this thing, but definitely cheaper than a new pack if you've got the time for it.
PS: Last thing, be very concerned about the condition of the wires that lead from the heater contactor, through the amp connector at the heater, and then to the heater element. If you're going to switch this thing to 230v, then the current going through those will be up in the 23 amp + range, and if the wires or connectors aren't very tight and in great shape, then you're going to be pushing the age old limits of them!
