Good point about using OEM fluid. You can buy the fluid at the dealer, or order the other MB approved fluid FeBi 02615 online, such as at www.autohausaz.com
Please do not use anything but the MB approved fluid. Other hydraulic fluids have additives that are bad for the seals in your pump and in the cylinders. We have rebuilt and upgraded plenty of complete cylinder sets way before their time would have normally come, just because people tried to save a few bucks on hydraulic fluid.
There was another good remark about marking where the lines go on the pump. That's a good idea. However, you can always retrace the lines' location by matching the numbers printed on the individual lines with the matching numbers stamped on the individual ports of the pump.
Also, the hydraulic line connectors going into the pump are about 3.3 mm thick. If you have a 1/8" drill bit (3.1 mm) ready when you take out the lines, you can save yourself from excessive oil leaking out of the pump. Put the dull end of the drill bit into the open port, and that should seal well enough when there is no pressure on the line.
Folks, the removal and re-installation is a bit tedious, but no rocket science -- you can do it! The dealer would charge you lots of labor, plus hundreds of bucks for a new cylinder, when our rebuilds/upgrades cost a fraction of new cylinders, and are actually better than new. No kidding.
Top Hydraulics rebuilds all hydraulic cylinders for all Mercedes convertibles, plus BMW and Porsche. They all use the same type of seal that fails in time. These are the same type of seals that are used in R129s. The statistics on R129 show an average life of about 10 years on OEM seals. Usually, the roof latch cylinders fail first because they get warmer up there in the roof, and the aging process gets accelerated.
The seals we have developed involve a PTFE back-shell (PTFE is the chemical acronym for Polytetrafluoroethylene, which is trademarked as Teflon by DuPont). They last far longer than the original seals used by the cylinder manufacturer. Our rebuilds are actually upgrades!
Just for fun, I'm attaching some before and after photos of a rebuilt R230 roof latch piston. The photo shows a plain Polyurethane cup seal being used as replacement, as this was one of our early rebuilds.
Hope this helps,