Just your common run of the mill Bell housing. Rear of Engine where Transmission mounts. Replace bolt and rotate cover back to cover the hole, one on bottom is a drain for leakage oil that gets into the flywheel area inside the Bell housing to keep it from accumulating. Basic any engine and transmission mounting stuff.
Rest of it will wait for someone familiar with the 8.3, I only drive them very occasionally. Shake, Rattle and Roll, not very impressed with them. Capable of shaking even a Crown so bad Crown had to add a fast idle switch to them since they were such nasty bus rattlers at low idle. Crowns DON'T rattle, but the 8.3's managed to bring it out in them. Shook everything to death. Not a fan.