If that was just a crack and a manifold worth fixing and you were capable of drilling the end of every crack it’s doable. But that thing is crack in many different directions and even after welding it you would have to magniflux it to see if you caught everything. Do yourself a big favor and write it off as a learning experience.
Great advice, we have become a throwaway society, buy cheap Chinese products, replace em every few years. I still believe in the good ol American craftsmanship from the past.
