Without the offset keys you won't get to 0° on the dot most likely, even with a new chain. The sprockets wear and this can cause it to be off a few degrees, but it usually isn't an issue. 2-3° of retard or advance won't hurt a thing.

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Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k