This car started up with 5 year old gas?
Normally people suggest a Bentley manual.
But I only see them for SC (78-83) and Carrera (84-89)
You want ZDDP oil. Racing oil with zinc.
a) 20W-50 Valvoline VR-1.
12 qts for $68.
b) 20W-50 Kendall GT-1.
12 qts for $45
The paint looks great in photos.
Can you post a close up of how the paint is not great?