ASA 5510 ugrade to 8.0 and current ASDM

I have successfully upgraded my 5510 to ASA 8.0. Yet I cannot get a successful load of the ASDM. I have downloaded from Cisco and uploaded to disk0: asdm-615.bin, asdm-61551.bin, and asdm-61557.bin, and the net result: “not a valid image file” Help.