Regal 3300 Owner's Manual page 151

Vessel Operation
TRIMMED "TOO FAR IN" POSITION
UP
DN
TRIM
TRIMMED "TOO FAR OUT" POSITION
UP
DN
TRIM
WELL TRIMMED "LEVEL" POSITION
DN UP
TRIM
!
WARNING
On stern drive boats, do not run engines above 1000 rpm with
the stern drive trimmed for shallow water maneuvering since
the stern drive is out beyond the gimbal ring side support
brackets. Operating in this manner could produce a dangerous
steering condition and could result in death or serious injury
and damage the stern drive components.
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