I'm about to do a 4 door power window conversion to my EL GLi. I got everything I need but do I need to upgrade the BEM to a higher up series? I've got a green one out of a fairlane sitting around, would this one work or do I have to use the blue one out of an EL futura?

Cheers.

The Fairmont and Fairlane BEMs have a different connector to the GLi/Futura/XR ones and will need a fair bit of re wiring in order to work in the lower spec models. So I would advise sourcing a mid spec (Futura/XR) one. Also it must be an EL one as the EFs have a different connector again.

You may not even need to replace it though... I'm not 100% sure, and I'd seek clarification on this, but in regards to the power windows the BEM is only responsible for giving you that 20-30 second delay from when the key is off to wind up the windows.
Maybe give it a shot with the GLi BEM and let us know?

no need to change bem, the power windows run on a seperate curcuit..