OK, had a look today at levelling of my twin tailpipe Cybox backbox. Initially figured bending the hangers would sort things but in short it won't - the issue seems to be that the box needs twisted from the centre pipe join back, but we've already used up all the play in the oval'd holes where the spring bolts go (holes in the backbox flange are oval).

Slightly unsure if perhaps we've fitted the centre section a little skew which has lead to the backbox then sitting skew aswell, or whether the backbox flange/centre pipe flange are out of line a little.

Current thoughts are that we'll have to drop the backbox off, drill the ovals out a bit more, refit it, and use the added play to level the twin pipes off...