Andrew,
Martin is absolutely correct, you must try to find out what went wrong before possibly repeating the 'orrible' exercise!.
Examine the PCB carefully and check each connection. Switch on the power whilst the platter is removed and check voltages at the 21V module. Check that the +27V is going to the correct terminal. Check the actual voltage on the wire.
Check the +9V and +5V outputs.

Before doing all this check that you have the + and - leads of you voltmeter going to correct terminals on the meter. (it can happen!!)

It maybe that all you have done, is to blow up one of the sub modules (9v or 5V)
or perhaps they are producing the incorrect voltage??

Now check the voltages at the PCB.

When soldering: always take the solder to the job.
Never ever melt a blob of solder onto the tip of the iron and carry this to the solder point.

The reason is that by the time you get the blob of solder to the job all the resin flux will have evaporated away and you will get a "dry joint".
I have seen countless problems caused by this.
It is very easy to secure the wire into the holes by bending over the ends if required before soldering. Although you will need to be very carefull doing this on the sub modules as there is not much room available on the very small solder pads provided.