DIY Doctor UK DIY Forums

I'm about to fit a new toilet. We've found one we want to buy, but how do I know if it'll fit between the wall and the waste pipe? The diagram and measurements aren't clear to me, and I asked the suppliers but they said they need to contact China for an answer? Am I right in thinking that toilets are universal and I'd just need to buy the appropriate 'elbow-what's-it-called pipe' to fit? Our bathroom and spare toilet waste pipes are at different distances from the wall, hence my confusion.

Thanks,