Based on removing the cylinder head from my ’83 300CD-T (Calif.) just over two years ago - a job for which Brian Carlton's advice was incredibly helpful:

I had the same problem. After determining conclusively that all bolts were removed and there was nothing whatsoever but a 25 year old head gasket and gunk keeping the cylinder head in place…

I used my engine hoist (bought especially for replacing the cylinder head) and (if memory serves me) attached a sturdy chain from it to three (or was it four?) points on the cylinder head. I applied a *moderate* amount of upward (pulling) pressure using the hoist, took a piece of sturdy lumber and repeatedly used my medium-sized sledge hammer to pop the wood/head from various vantage points. After 20-30 strikes as I recall, the head was released from the block. BE CAREFUL: when the head comes loose, it will pop up due to the tension applied by the chain/hoist. KEEP YOUR HEAD SUFFICIENTLY CLEAR OF THE CYLINDER HEAD AS YOU ARE STRIKING THE LATTER.