Turbo re-build, IDM upgrade, Moderate knock in #8???????

[EArmsF350]

Well I got screwed out of a low mileage cab and chasis because my boss drug his feet too long to upgrade and the big dogs told him he cannot trade now, so my $1000 cab and chasis with 167k is down the crapper. My problems and questions.... #1 Should I put a re-build kit in my stock turbo wen I fix the up pipes and install the WW or just leave it alone and replace the compressor wheel. #2 My truck has always had a terrible throttle response and appears to be on limp mode (very slugggish) Beans Deisel in Tennessee has an IDM upgrade +15-30 hp for $100.00 Is this something I should try or tell me the pros and cons of the upgrade. Truck is all stock except for intake and exhaust. Have gauges though. #3 I have always heard what I would call a moderate knock in the drivers side rear of the motor. Appears to be in the #8 cylinder. Put a new injector in it and still knocks. I have heard wrist pin, or rings. Looked at sticky titled bent push rod and knocks associated but I couldnt get the video to play. Coments needed. Thanks. 12/1999 F350 auto. 227K 4x4