1996 Bonneville 3.8V6 - needs motor

I am new to this forum and am hoping to receive some feedback on changing out a motor in my bonneville. Just bought a beautiful car, and it seems that I need a new motor. Using oil faster than gasonline, just coming right out the exhaust.(However, I wasn't aware of this at the time of purchase). I've found a motor, but don't know much about 3800 motors. Any suggestions with things to watch for or any tips. Feedback will be appreciated. Would like to know if anyone else has found themselves in the same situation as I have. Thank you