Here are my choices. The blue manifold looks good.
The 2 headers both have issues. The original ,(no extra flange) just needs to free up the heat riser. Fingers crossed. And 2 mounting bolts for the pipe. The modded one has no heat riser and pretty well pitted. Maybe more problems.
Any good options there?
I would go with the original, and free up the heat riser. That will take an extra tool from you tool kit called patience. Hit it with a penetrant, then “tap” the shaft back and forth with a small hammer. Try to turn the weight.
DO NOT FORCE, or you will sheer the weight off of the shaft. Repeat for several days! If that doesn’t work, try heating the area around the shaft to about two hundred degrees then soak it with penetrant while its still hot. The heat will help draw the penetrant in. Use a good penetrant like Kroil or PB Blaster. If you keep the temperature down, to two hundred, there will be no danger of fire and of cracking the manifold.
The modded one is trash. The only thing it would be good for is the flange so you can make the dual exhaust manifold the right way as HRL has suggested.
