I don't own this card anymore, but here's what I did when I did.
This is a G3 upgrade card for PCI based Macs, including the 7300, 7600, 8500, 9600 etc.
I've seen several reviews for this card
that mention the flimsey clips that only just keep the heatsink in
place. Mine came off in the post and I couldn't get it back on.
You'll find that a heatsink from any original 60x based card will fit
nicely. You'll just have to cut a chunk out so you can get to the
speed adjust dial.
It's a good idea to use some thermal paste on the CPU too, the non setting kind.
ABOVE: The G3 card with the 604 heatsink fitted. And that's the original black heatsink on top for comparison. You can also see the cut-out where the dial is at the bottom.