Up for sale is a good used Saab 9000 Fuel rail.  This is from a 9000 Turbo Trionic 5 car.  Includes 3.0 bar fuel pressure regulator.  This fuel rail has about 2 times the volume as the standard classic 900 2.1 & 2.0 fuel rails.

These are easily adaptable to the classic 900 models!  All you need to do is bend 2 tabs, and get a stud & bolt kit - the "stud kits" eeuroparts sells for the exhaust manifold bolts work perfectly for this.  Please see my pictures. 

If you do a trionic 5 conversion on a classic 900, plug in your diagnostic tool, and you may notice the knock counts on Cyl #1 are higher than any of the others.  The reason for this is that Cyl #1 is the furthest from the fuel supply, and has the longest exhaust run.  The small diameter fuel rail is a major contributor to this, there is a slight pressure drop in the rain, which gets worse the further down the rail from the feed.  Cyl #1 is the most distant from the fuel feed.  The Trionic boxed fuel rail helps to correct this, by having a "fuel sump" volume of more than 2X that of the standard round rail, there is no pressure drop in the more distant injector when you are at full throttle.

The standard round rail was never intended for more than 185HP.  You start having slight pressure drop problems if you run above 200.  By 250, there is a serious problem with the stock fuel rail on the classic 900.  Don't toast your rings or pop your head-gasket because of this easily correctable issue.