It would take me - a non-mechanic - 15 minutes tops to do the both sides (4 bolts per side, you do need to unclip the plug wires, and the breathers on each cover). I'd imagine a mechanic would bill for no more than 0.5 hours. Plus parts markup unless you supply the gaskets - which on an older car like this may be advisable, as sources that most mechanics have won't get them in stock within a day or two.

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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