Fitting a Lithium coin battery to A4000

[RMK305]

My A4000 mb is off for a repair and I'm looking for information on putting a lithium coin battery in place of a rechargeable barrel type. I contacted DJBase who has sold out of his adapter but have since found this one on the Bay:

http://cgi.ebay.co.uk/COIN-LITHIUM-BATTERY-BACKUP-AMIGA-4000-3000-2000-/220775148701?pt=LH_DefaultDomain_0&hash=item3367396c9d

Does anyone have any experience with this one or can someone tell me or provide a diagram of what is required to fit one of these types of batterie to the Amiga without the machine trying to recharge it?

Thanks for the help.

[RMK305]

Thanks Mechy,

The other option is to get the one from Amigakit and get the repair guy to fit a diode. Where exactly does the diode go? There are 3 holes from where the barrel battery was attached. Going this route would save time and get the board back to me sooner...I'm keen to start building it back up with my new parts

http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=724

Thanks,