new outlet in hot water cylinder

[shouldknowbetter]

I am installing a shower and want to run a dedicated hot water supply in 22mm pipe to the pump. The cylinder is covered in a hard foam insulating blanket and I don't want to break it off to see if there are blanks / cutting points. Where on the cylinder should I cut the hole for the new supply?

Many thanks

 

[namsag]

There wont be any blanks buy a surrey flange that fits into the top of the cylinder in place of the existing connection. the existing pipe into this will need a slight alteration to aswell