What I always do is to leave the ignition key off and then, using a remote start switch, activate the primary on the starter solenoid.
With the key off the ECM has no power, the lift pump has no power, the injectors are not active, nothing is active.
On most early 3rd Gen trucks, the starter primary wire is easily accessed by the fuse box in front of the drivers side battery.
It's a larger gauge yellow wire.
There is a connector there you can disconnect, then connect the starter switch to 12V and the yellow primary wire.
Try to pour some oil down the oil feed ports of both turbo's also if possible.
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