Adjusting the piston...

Take the old MC out, measure how far the piston rod sticks out. Cross your fingers & hope the new one is exactly the same. If it isn't there's a special measuring tool so you can adjust the pushrod down at the brake pedal. Exact details might be different from year-to-year, so I'll just suggest you get your hands on a Helm book...

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Bench-bleeding...

Get some tubing to fit where the steel brake lines are gonna go, looped up so they squirt into the reservoir.

Clamp the MC in a vise or something, just to hold it. Fill the reservoir, pump the piston rod until fluid keeps squirting into the reservoir without bubbles.

Be prepared for a bit of a mess when you install it into the car.

If you don't do this, it takes FOREVER to bleed the air from all the little hangout places inside the MC. But it can be done without bench-bleeding.