How to convert ProE files to Solid Work

I want to develop an utility which converts the ProEngineer files to Solid Work.

Files to convert are sheet metal files.

Converted files should be editable with the full tree structure into solid work.

I have tried with Import option but it deos not convert tree structure.

Imported files can be able to edit.

How to startup the conversion with developing the utility for ProE and Sloid Work... ??????