Here's how I go about determining a safe running range. Start with an empty oil pan and add 3 quarts of oil. Position the stick so the level aligns with the "add" mark. Adding another 1 1/2-2 quarts should bring the level to the "full" mark on most dipsticks unless you've got an oddball pan sump volume. Most canister-type oil filters such as Fram or AC retain about 1/2 quart after several hours of the engine not running, so 4 1/2 quarts in the pan usually puts the level at full on the dipstick.
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!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!