It makes it less costly overall if you do them both at the same time and if it needs both.
I had mine replaced(the actual cover due to an updated design) with the headgasket and then thats when the wiring harness gave me fits. But I went on to accumulate more than 100k mile with NO problems!! Im still missing my car as i sold it with 241k miles on it and it ran just a good as when i bought it. I think if you pony up the money you wont be disappointed in the long haul. My w124 with the miles felt more solid than the 41k mile jaguar XJR I just purchased. They are truely an IRON vault.
Im pretty sure my next car will be a low mileage E500(94-95) variety.
Chris

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94 E320 with:
18" ///AMG Monoblock II's,AMG Gen II front bumper, H&R spings,500E sway bar, Bilstein sports, Eisemann Exhst, K&N,E500 Headlamps, Crystal Clear Corners, Avantgard Grill ...and more stuff to come! oh yeah 241k miles!!


My Car WOO HOO...... Now SOLD
New car.... 2001 Jaguar XJR!!!!