Bad bad bad HD

[Thing]

I have a Maxtor D740X-6L 40GB HD with a bad logic board and need to buy a HD with
a good board so I can swap them out and get the data from the bad drive.

I found one on ebay that is an exact duplicate with one exception.  On the back of
my drive, this is stamped:

AVQ3
0570

On the back of the drive I found, this is stamped:

AVQ3
0540

Here is a pic of the ebay drive:
http://images.auctionworks.com/hi/58/58321/30273.jpg

Sooooo my question is, do any of you hardware tycoons know whether or not this will
work for my purposes?

[Grok]

I have done that before with a Maxtor drive a few years back.  Although it was a 200MB drive, the procedure was successful.

[Thing]

Well I'm going to go ahead and bid on it.  Hopefully, the different numbers stamped on the back are meaningless.  Everything else looks correct.  All the chips are in the right places, etc.  If it works, I'll be happy and so will the lady who owns the original HD.  Maybe she'll repay me with a hug and a six pack of beer.

[Thing]

Update.  I actually found the HD's sibling.  All of the numbers matched exactly and I bought it.  I swapped out the logic board with the newly purchased one and it worked.

Data recovered.
Hug received.
No beer love though.

[Adron]

Update.  I actually found the HD's sibling.  All of the numbers matched exactly and I bought it.  I swapped out the logic board with the newly purchased one and it worked.

Data recovered.
Hug received.
No beer love though.

What happened with the one that almost matched?

[Thing]

I didn't buy it.  I wanted to try and find a perfect match first.