I had the same problem on my Craftsman GT5000 Model 917 276050, big hole in the back of the tank so likely not repairable. I searched online for the replacement part #179115 but it is discontinued. Looked in junkyards in my area and could not find it, an old tank may end up cracking soon anyway. Ended up using a fuel tank off a different model craftsman, part # 151346, about $60 new online. Its the same shape as the original tank minus the portion that sticks over the left rear wheel. The original bracket over the top of the tank is the same. The fuel filler neck is in the rear so I had to cut a hole in the fender behind the seat(used a jig saw with metal blade). This was the only modification other than zip ties to hold it down a little tighter, this may not even be necessary because when you bolt the fender back on it sits on top of the tank and holds it in place. I filled in the hole where the old fuel cap was with a cup holder and good to go. I will post pics later.