This is an e30 M42 manifold - What you want - Also found on SOME early e36's that came fitted with an M42 engine
..and this is an e36 M44 manifold - What you don't want

Notice how the centre two exhaust runners on the M44 manifold sit a lot lower and merge a lot later than on the M42 manifold.
In situ these will interfere with the steering column linkage on your e30 and cause no end of fun.. And yes, while you can "make" this work with a love tap from Mr Hammer, it is far from ideal as you're restricting the flow of the exhaust gases and cocking up the harmonics. Which on this peppy little engines is the last thing you want to be doing, so always worth hunting out a proper M42 manifold.