It won’t be the distributor or the spark plugs. If it happens when you turn the key to the start position to crank the engine it could be the starter solenoid.

Not sure what work you did on the front-end, but it's always worth starting with the wheels and tyres when you have a vibration of that type. That's the most likely cause of the problem.

It does sound like it's a brake problem and should be able to be fixed by a brake specialist. You could also take it to a competent mechanic, who should be able to fix it, or a Ford dealer