Sheathing

[cabinboy]

I am building a cabin that is 32 x 24 using room in attic trusses. The question I have is when I sheath, should the sheathing come right to the outside edge of the gable truss? The reason I ask is that I see all the houses around me that do not have overhangs on gable ends have at the minimum a piece of molding so the end of the roof is at least 1-3 inches over the outside wall. My assumpion is that this is to have water drip over the edge rather than straight down the siding. So what I am planning to do is sheath to the edge of the truss, put a piece molding that buts up to the sheathing and then cover with felt and shingles. Is this correct way. It seems that If I sheath over the molding that it would be a boatload of ripping the 4x8 sheathing.

Thanks