YES 5.9 Magnum manifolds work in early A bodies. Here is exactly how!

Perfect, glad someone made the effort to document the fit of these fine cheap *** manifolds! How hard was it to press out that pin? I had to grind the casting numbers off a pair of B hi-pos to fit, I get tight fitting parts....

3/4-36 to 3/4 smooth is Sweet Mfg 12-06 combo, and not that common...
Steering Universal Joint 3/4 Smooth To 3/4-36 Spline Steering Shaft Or Rack And Pinion - Kartek Off-Road