A comprehensive immigration reform bill being drafted by the House’s bipartisan “Gang of Seven” is progressing without any major hiccups, but members refuse to be rushed while working toward legislation both conservatives and Democrats can get behind.

No deadline has been set yet for introduction of the measure, and action this summer is looking unlikely.

“They are going title by title and there haven’t been any major problems as of yet,” a congressional aide familiar with the discussions told International Business Times. The bill, which has been in the works for about four years, has stalled many times over issues such as health insurance.

Though a comprehensive bill is near completion, House Republicans will have to decide what to take to conference with the Senate, which has passed a package, once the measure is unveiled. Currently, most House Republicans favor a piecemeal approach to immigration reform, focusing on border security and interior enforcement. None of the five bills passed by two House committees tackles what to do with the 11 million undocumented immigrants currently in the country. The Senate bill, which passed last month, puts them on a 13-year path to citizenship. Conservatives in the House are opposing a special pathway and are refusing to take up the Senate's legislation.

The House gang will need to produce a bill that bridges that gap between the two sides, or at least bring forward a measure that is middle-of-the-road but tough enough to get conservatives to buy in. Any result that is less than tough on legalization, a concept conservatives reject, could leave it vulnerable to attacks, even if a Republican as prominent as House Budget Committee Chairman Paul Ryan of Wisconsin has shown signs of openness.

“If they take something to conference like these piecemeal bills, obviously the pathway to legalization is left out and so in conference the Senate pathway becomes the go-to,” the aide said. “I would think that Speaker [John Boehner] would want his conference to weigh in on that, to give the opportunity to the entire House to weigh in on that aspect because it is a key aspect."

Still, an apparent lack of leadership strategy among House Republicans is a concern.

“There are a lot of very loud voices on the far right who … are taking up a lot of the airspace right now, and that’s fine,” the aide said. “I think the Republicans in the House need to sort of talk through that and debate what approach they want to take.”

Immigration reform, as envisoned by the House gang, will contain principles similar to those addressed in the Senate bill, but with a tougher path to legal status so as to appease conservative concerns.

Another congressional aide said the "Gang of Seven" has been paying attention to many things such as how reform “would happen across each of the states because sometimes it deals with state laws and all the states have different ways of doing it.”

“They are not rushing a bill out,” that aide said. “They are trying to get the bill right and get it out.”