I'm building a tarp of SOL "Survival Blankets". The main body will be about eight feet long, but there will be a bit of an overhang on each end (I think this is called a beak, but not sure if that term applies unless it slopes downward to the ground - mine don't slope down). To get an idea of the shape I'm talking about, it should be very similar to the MSR E-Wing, only with a bit different proportions. I'd originally planned to make these overhangs at least two feet long or more on each end, making the total length 12 feet, in order to keep out more rain, but decided to make them 16" on each end in order to save some of my survival blanket for another project. However, after attaching one side of an overhang on one end, visually, it just seems very short like it's not going to keep out the rain, but I'm hoping to hear from more experienced tarp users. Is 8' plus a 16" overhang on each end, for a total length of 128" at the ridge line enough to keep out the weather?