Many have mentioned a repair tape they keep in their tool box for emergency repairs of things like hyd hose, fuel line etc. Don't remember and can't find in search of "repair tape" what the brand nam...
Thanks for all the info, may just end up replacing tank. Neighbor has same issue (bought the same brand tractor as me) and we are going to look at best way to repair if possible. This should be fun - how many engineers does it take to fix a garden tractor fuel tank???? :-)