You need to attach the heatsinks with special glue made for this particular purpose. I use something called Artic silver IIRC.
Regarding the extra power, you attach it where the fan gets it's power from. Find an Y power lead, snip one of the connectors of and take one +5V and one GND and solder to the fan connector. Remember to attach the wires to the right place (+5V to the +5V lead and GND to GND, otherwise you will blow the card). And don't use +12V, it will blow the thing up as well. Remeber to still feed the fan on the Blizzard board, there are several ways of doing so.
And yes, if it is a SCSI version, it does make a difference, as these boards needs more power on boot up than non-SCSI boards. I hope it helps you out, and if you can't do the soldering yourself, then get someone else to do it :-)