Basically, you need to take it apart to the extent that you can get the main PCB out. This means removing the case and jack panels so that you can un-nut the PCB and remove it. Install the new battery and reassemble.
Here's the battery I use:
http://www.radioshack.com/product/index.jsp?productId=2715655Good luck, Mark!
--- In Simmons_Drums@yahoogroups.com, "Mark Frost" <airflamesred@...> wrote:
>
> I'm sure mine must need changing after 15 years. Whats the procedure? I'm thinking Maplins will have a replacement - would that be right? And if anyone has a part No or any other info I would be gratefull.
>
> Thanks in advance.
>