[RAF_Magpie]

I think you'll find the problem with using the top turret, as you and others have requested in the past, is not exactly possible - due to how far the gun can depressed - not below the horizontal... So if you had this in the nose position, you couldnt depress it far enough.

The tail gun from the '25, as Raptor has suggested, would be the best bet for a decent replacement, unless someone can actually mod the TURRET itself.