How do the majors parties differ on EU policy?

Historically, the Conservatives were pro-EU taking us in, in 1973 and Labour was anti-EU under Foot seeing it as a 'Capitalist club'. Since then, the tables have turned as the EU helped topple Thatcher and Major and unify Labour.However the differences between the party have typically been seen through rhetoric as opposed to action. The Conservatives have typically spoken tough on Europe to feed British euro-scepticism, but this has done little more than create problems and divisions for the party internally. Labour has been more inclined towards the EU after Blair announcing he wanted Britain at the 'heart of Europe'. The most pro-EU party typically however is the Lib-Dems. Ultimately, the Conservatives were in government when the single market was established and Major passed Maastricht in 1992 although he did add in the subsidiarity clause. Labour spoke about the possibility of joining the euro but never did anything so both parties seem to be in some sort of political limbo.Similarly, both parties have factions of euro-scepticism although of course the Conservative faction is the sizeable group. The recent rebellion of 114 Tory MPs over the inclusion of the EU referendum came because Cameron in 2005 while standing for leader of the Conservative party promised to peel back Lisbon but hadn't and so his backbenchers wanted some kind of guarantee of this referendum if the Conservatives win the next general election. There is also this push for a stronger stance on Europe from the Conservatives because of the UKIP threat who got 1 in 5 of the vote during recent local elections They lost their motion due to Labour not supporting them. The creation of the 'Labour for a Referendum' group saw 20 Labour MPs put pressure on Miliband to offer an in-out referendum.The main difference between the two parties is the referendum. Cameron announced he would offer the public a referendum in Jan 2013 saying it was time for the British people to have their say. The referendum would come 2 years into the second term after Cameron had renegotiated Britains relationship with Europe. He hopes to peel back things such as the European arrest warrant which places him at odds with Clegg and his coalition partners. Cameron has already announced he will opt out of 140 EU law and order measures despite the President of the European Parliament, Martin Schulz saying 'Cameron's Europe a la carte is not an option'. The scope for renegotiation seemed minimal until Merkel sided with Britain in recent budget talks but even then the Danish Prime Minister said that the UK and Denmark were now on 'two different paths' in  Europe.Following the announcement of the EU referendum, Clegg changed his tune and said  "My party has always believed there should be a referendum on Europe when the rules change," he said. "By the way, I think it is a question of when, not if, because the rules are bound to change." Even some commentators are not ruling out Labour announcing it will promise a UK referendum this is purely because of the UK has always been particularly euro-sceptic and the major parties do not want to isolate any voters by seeming aligned with Europe. Milibands initial reaction to the referendum announcement was however that it was 'wrong' and damaging to business, a view supported by the US who want the UK to remain in Europe.Both parties however have always been more inclined to the US-UK relationship than the Europe-UK relationship despite the fact 40% of our trade is with Europe. Blair supported Bush during the Iraq war despite French and German objection and European attempts at any coherent defence policy usually led by the French has been hampered by the UK's attachment to the US through NATO. The UK has always preferred to align itself with the US rather than Europe and that is a similarity for the major parties.