Hey man, if you can see that hole aweeping, you must have an eyeball at the
end of a stalk that is more than a foot long. Tighten up any bolts or nutz
that attach the pump and dump in  some stop leak to seal any gaskets . If
this works, the pump is good, and you can forget about the rest. If not ,
it is the pump most probably. It takes about 10 hours of labor to change
that pump as you know.