Well, the simple answer then is to get some engineering support. Get the job done properly as some airlines already do.
EG USAIR A330. All landing gear doors are extended each layover check for a thorough inspection. No risk as long as you have engineering personel (who know what they're doing) to carry out and certify the task.
The 747 body gear bay, by the way, is clearly visible with a good torch and an average size person standing on the wheel rim. The wing gear is another story.
