25yr old
Drive a 6speed Laramie 08 3500 megacab dually
H&s deleter kit
Straight pipes 4"

I'm not sure if the throttle door deal has been modified

I bought it like this. I have no tuner. And no sims. I've driven it about 1500miles with the power reduced message.

Any suggestions on what kind if tuner I should get? Does it have to be the same kind as the previous owner had?
How long until the motor explodes from driving it on reduced power?