I have a 1971 corvette with a 454. The starter is new/rebuilt from GM. It started fine no problems for about 20 or so starts. The last time I went to start it, turned the key, dome lights dimmed, nothing happened. Assumed it was a bad starter. Took it out, an bench tested fine! Reinstalled, car started just fine. 20 or so starts later exact same thing. No sound, lights dim, owner frowns!

A couple of things to check..

Since you did not have your starter rebuilt.. you may have gotten hold of post 75 starter.. there are differences.. the pre 75 have heavier windings and the copper tab to the solenoid is in a slightly different location. Also there should be a heat shield on the solenoid. You didn't mention if this happened after the car was hot or cold..

If this occurs when cold.. remove the starter and check the armature shaft.. it could be fractured.. it will work on the bench just fine.. but eventually under load.. will fail..

Obivously check all connections..cable condition.. and especially grounds.

Lastly.. it is not unsual for the auotpart store books to cross reference the wrong starter for these big blocks.. some starter replacements are often wrong for the year/motor and will extend the starter gear too far...

Good luck