Acts like a bad starter. Bendix won't engage

What is your question?

Pushing in the clutch to start requires pushing to the firewall as hard as possible. Is there an interlock starting switch that is adjustable so I don't have to push so hard? Is it under the dash or under the hood? I have replaced eight(8) starters but have fewer the 70,000 miles? Any help or advice will be appreciated!!

What makes this problem better or worse?

Pressing real hard in the clutch helps. Not hard, the starter spins but the bendix doesn't engage

How long has your 2001 Nissan Frontier had this problem?

Started about 2-3 years ago.