My 70 dart thinks she's fat.

Look for all the "low hanging fruit" so to speak. All the stuff you can remove or swap out with lighter components. Is it gonna be a street car? You will still need horns to keep it legal. Get a single Hi Note plastic horn off a late model chrysler vehicle, ditch the cast aluminum and steel dual horns.

Move battery to the trunk. It's not removal of weight but is relocation of it.

Get a torch and heat and remove ALL that black asphalt based undercoating /sound deadened in the wheel wells, inside the doors, rear quarters, and under the car. That **** probably adds a good 25-30 lbs to it.

Get some thick aluminum plate. Trace your alternator brackets onto that and cut it out. Ditch the steel for aluminum. Add a circular lightening hole in the middle of the triangular bracket.

Hope this gives you some more helpful ideas.