The floating pickup is correct for some late model engines. I don't remember exactly when the change was made, but it was somewhere in the late 1950s, I believe. It shouldn't be rattling under any circumstances. Is the screen in the pickup able to flow oil freely at higher speeds (not restricted or clogged)? You could temporarily lock the floating pickup with a piece of stiff wire or a hose clamp to positively eliminate it as the source of the noise.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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