Afew more questions for the group:
- Intake manifolds: See photos per comments above.

- Timing Chain covers: Can these be cleaned with Scotchbrite and degreaser? I did a test patch and it appears that these are actually too abrasive leaving scratch/streak marks. Any recommendations?
- Oil tank: I will have it flushed and repaint with high-temp 500 degree paint. Do these need pressure testing?
- Casting/stamping codes. What do these various numbers mean? Dates?