whats the best way to jb weld a fitting to an oil pan would i have to rough up the back side of the pan and just apply the weld there or should i do front and back? anybody have pics or know where i can see some of oil pnas like this... i have a 5/8th barbed to 3/4th male pipe fitting that i need to attach to a steel oil pan

 

You could do it right and get a bit and tap set. That is what I did man did it work great, plus I put a little jb weld on there for good measure.

But yes you could just straight JB weld it. You would want to clean and scuff the surface that will be bonded. Look at projekteg's. I think his might be JB welded still.

 

anyplace where there's a welder won't charge you more that $15. tops! to weld on a tube to your oil pan.