and just in case anyone wants to know what I did....
I put it all in a nice plastic pocket folder. Nice cover letter, a place for the completed SET (M) and attached check, a 1.5 page outline of what was in each document section. I divided it into primary doucments and secondary, with secondary being further subdivided with each sub-section having it's own pocket. Primary included all our passports, Drivers licences, marriage cert and last three months pay slips to help show financial situation and no need for public funds. Secondary was everything else from National Trust membership letter, more wage slips, banking info covering the last two years (not every statement!), plane ticket iterinaries, tax/Inland revenue info, local Plymouth city stuff, NHS letters, DSA stuff , bills, deeds and title to the house, and anything and everything official looking I could gather for the last two years. It was over an inch and a half thick! Probably over kill as it was double the documents they needed, but hey it's all organised and tidy!
I sent it off special delivery!