1990-1994 Chevrolet Lumina
Ground-Effects Kits

In my opinion, the factory ground-effects on the Lumina Z34 is one of the best and cleanest looking you can get. It should be possible to add Z34 ground-effects to any regular 2-door Lumina. This would require getting ahold of the ground-effects on the sides and doors, as well as new front/rear bumper covers. It would also be possible to do a full exterior Z34 conversion on a regular 2-door Lumina by getting ahold of the ground-effects, Z34 front/rear bumper covers, Z34 taillights, hood, rear wing, and "grille". These parts can be found for the best prices at auto salvage yards. They can also be purchased brand new from any GM dealership.

Ground-Effects kit from Erebuni Corporation Style 117.

Erebuni Corporation has a complete ground-effects kit for the 1990-1994 Lumina 2-door that has Ferrari Testarossa-style ridges. The Erebuni kit is definitely a radical design that makes the Lumina look very different. This kit is not compatible with the Z34 and 4-door models.
Erebuni Corporation, Style 117.

Ground-Effects kit from Razzi, Part #034-100/#034-200

This is a good looking kit with smooth front/rear bumper covers that comes in both 2 and 4-door versions.
Razzi, Part #034-100 (2-door), #034-200 (4-door)

Rear Wings
The following rear wings are custom designed for the Lumina.

This is the Lumina Z34 factory wing. I believe it will fit on any 2- or 4-door Lumina.
Factory Z34 rear wings can probably be found used at auto-salvage lots or purchased new from any GM dealership. They do not have a brake light.

This is the Lumina Euro factory wing. It is flush-mount and wraps around the entire rear and sides of the trunklid. It will fit on any 2- or 4-door Lumina.
Factory Euro rear wings can probably be found used at auto-salvage lots or purchased new from any GM dealership. They do not have a brake light.

Universal Wings
If you don't care for any of the above rear wings, you may want to choose a Universal one.