If you're new to the game I advise carrying plasters for those innevitable cuts you're going to get and a pair of tweezers for removing splinters.
They've come in handy for a good few times and they don't take up any space.
Oh and a telescopic magnet (size of a pen) for reaching those tiny...
If you go to a B&Q you can play with the fittings there and I'm sure the resident plumber would be glad to help. Use push-fit for the stand pipe if you like but I'd recommend solvent weld in any inaccessable areas.
Follow these steps.....http://www.brettmartin.com/building/soilwaste/technical_guide/installation/solventcementjointing.aspx
Still not sure? Post a couple of pics.
EDIT: Is the boxing in the dining room plywood or something similar which you could widen?
Use a stand pipe and do it the good old fashioned way leading to the drain outside, if you have no drain out there connect the waste hose to the sink trap. Failing that post a photo.
It looks to me like it was put together out of odd bits found round the site when the house was being built. Botch job? Absolutely!
Is that a party wall? If not I'd take it out through the wall instead of the roof.
Have I missed something here? Do you want an electric shower where you just have the dial on the wall or do you also want it to be wireless in some way? Forgive me but the last few comments have totally thrown me.
If you mean just having the 'knob' on the wall then check out MIRA.
http://www.mirashowers.co.uk/home.htm
EDIT: Never mind, just realised you want electric. :roll:
This is a swan neck connector (or space saver) as mentioned before but from what I can see in you pic it probably won't make a difference to how far forward your new pan will be. In other words you don't have a choice unless you're prepared to go back on your word and dig out the floor.
Mostly fitting washing machines, hobs and capping off gas fires lately, really quick and simple jobs. I'd love to just get a full days work in to be honest and I'm considering doing an electricians course because I have so much time on my hands.