| Hello NigelC.
When putting my pipes together I found that working from the crank put all together that you can. So all you have left are the end pipes in my case termmi's undo the rear two bolts of the sub frame this will make things easyer. Lift up the sub frame and at right angles to the bike attatch the end pipes then swing them around into position not forgetting the baffle clips.
Hope this is of some help if all goes well you should not need to hit any thing, the most common mistake is getting the right end pipe on the right down pipe..
I hope I have made myself clear if not do a search this topic has been covered before.
regards
TopiToo | 
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