This is not a complete intake manifold removal, this is a few tips that will help you remove the E36 M52 intake manifold.

My favorite Manifold Removal DIY is by M3NACE : https://www.youtube.com/watch?v=J54rKGFWwAA&t=603s

The intake manifold really isn't very difficult to remove in my opinion, however it can be a real POA if you dont label everything or you forget to disconnect a bolt or bracket.

The most difficult part about it in my opinion is re-connecting all of the vacuum lines during re-installation. The best way I found to do this is to loosely fit the manifold on, and then re-connect them with the additional space.

Be extremely careful with the fuel injectors, as the plastic connectors are extremely fragile.

Take a look to identify if you have the two brackets that hold the manifold in place, they are 10 mm sockets.

For the M52 removal you DO NOT have to remove the wire harness. By removing the wiper cowel, you give the manifold enough space to maneuver out from under the harness.

Take time to label all of your hoses and connections, and you'll be fine.

Things to replace during this process:

Vanos Oil Line
Oil Pressure Sensor
Vacuum Check Valve
Vacuum Hoses
Coolant Temperature Sensor
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Intake Gaskets
Fuel Injectors?
Intake Manifold Temperature Sensor 
Knock Sensors?
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