You shouldnt sand if within the window of time per the manufacturer.
If outside that time, or if very dusty, you can sand.
It should say on the can
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- 70 Fastback Mustang, 489 cid FE, TKO-600 5 speed, 3.70 9 inch
- 71 F100 shortbed 4x4, 397 cid FE, headers, Street Dominator, 280H, 5 lug Dana 60, 4 speed
