Don't convert the current system. Just buy a good used rear struts and replace them. If you converted it and you want to sell the car in the future, it will lose so much in its price. Maintaining the rear hydraulic system is not a big deal. I would spend much money rather than converting it.

My car is 560SEL 1989 with FULL hydraulic system. It's driving me crazy and so much money I'm spending but still did not convert it to regular.

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Master Computer Engineer, A+, Network+, MCP/MCSA/MCSE 4/2k/2k3 - Messaging, MCTS, MCITP, MCT, Brainbench, ICDL and starting Ph.D

380SE 1984 <------- Totaled by flipping accident
300SE 1988 <------- Sold
Volvo S70 2000 <---- 4 family
Opel Omega 2002 <-- 4 family
560SEC 1989 <------ Sold
560SEL 1990 <------ Sold
560SEL 1991 <------ 4 my mother
560SEL 1989 <------ Sold
600SEL 1992 <------ Current

http://search.ebay.com/_W0QQsassZkhazenzcc