Looks like my note to step 3 appears on all repair guides that have the same step. I meant that in the context of the hard drive replacement only.
Did you have removed the optical drive without removing the battery ?
I haven't yet done anything, waiting for my MacBook Pro 15 inch mid-2010 to arrive.
Question: why do you remove the battery? According to Apple's official manual, this is not required (not for the mid-2009 and not for the mid-2010 15-inch MacBook Pro) - see pages 37 ff: