You don't replace just the bolt, but the whole LCA bushing, and to do that without removing the kingpin from the LCA bushing is impossible. When you do, the hub assembly will simply fall, so it's easier to remove it to prevent that.

To not remove it all and do it would be tricky, and since it'd be so tricky it'd also be very very dangerous. I've done dangerous work on the front suspension, using the car's weight to compress the spring, but Tassie, what you're looking to do sounds suicidal.

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2021 Charger Scat Pack Widebody "Sinabee"
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1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
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