How do you install Revell 40 Ford bumpers

[Ranchwagon]

I'm building a Revell 40 Ford coupe for the first time and I'm wondering what the best process is to install the bumpers:

1. Install the bumper brackets to the bumpers and eyeball frame mount alignment, then install to the car?

2. Install the bumper brackets to the frame and eyeball bumper mount alignment, then install to the car?

3. Or is there a better way???

Thanks

Kerry