When comparing 2 post vs. 4 post lifts I see that 4 post lifts appear to have a bar located below the engine compartment that would hinder engine/transmission work. Is this the case?

I'll be using a purchased lift for vehicle work not for storing a car.

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JWJ
1983 MB 300D - > 430,000 miles - Deep Blue - Bilstein Comforts - 0-60 in 24 seconds - 27MPG
1985 MB 300TD (wagon) - > 275,000 miles - Manila Beige - Thule rack - 0-60 in 18 seconds - 22 - 25MPG
Biodiesel, Mobil Delvac 1, and Viton fuel lines!