If you choose to remove the new starter for bench testing, there is plenty of room to use a pry bar on the flywheel teeth through the starter hole to engage the teeth. With that amount of leverage available, the engine should turn easily. It's still simpler to use the weight of the vehicle to bump the engine over by putting the transmission in gear and pushing (by hand). Don't get tempted to tow the truck and pop the clutch with the transmission in gear- - - -you can break an axle, damage the transmission, or bend connecting rods if the engine is seized up tightly.
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!