Thank you Brendan
For those links,and advice-they look quite a good job.
I'll following up on these,and have a play around with the camera (a Canon 40D) as is,for a while,then try one of the mods in your links.
I am then thinking I might look at doing a cold finger cooling mod,I notice @Mill has done a great job,and there is a bit of info in his 2009 link.These cameras a basically worthless now,so might give it ago.