I think Larry meant 'do one caliper at a time'.
If you were to pull both calipers off, then compress the pistons on one of them, the pistons on the caliper on the other side might pop out too far. Don't bother asking me how I know this...
For a multi-piston caliper, it is nice to have a 'pad-spreader' tool to retract the pistons.
I have a couple that resemble a small scissors-jack. I think this type works best.
1986 300E 5-Speed 240k mi.