Replaced a whole mess of items on my 98 gmc 1500. Now it is making a super loud, rhythmic squealing noise from inside the motor. It’s not the belts, I checked. I replaced the distributor, spark plugs, wires, catalytic converter assembly, all four o2 sensors, muffler, radiator, fuel pump, fuel pressure sensor, and crankshaft positioning sensor. I have the mechanical inclination to have done all this work in good faith of myself. I followed all direction I could get my hands on. I was told by a boss of mine that builds track cars, that even if I did my timing correctly there was still more to do. I’d like to be able to fix this problem myself, but my back is against a wall. I’d like to know if I should have it looked at by someone more qualified than myself. Or if it’s even worth holding on to. I really do love the truck but I also don’t want to be turning out my pockets.