Mercury 40 Force shift connector siezed

[mercurymang]

I attempted to replace my water pump impeller yesterday. When I attempted to disconnect the shifter linkage between the lower and upper units, the connector would not thread upwards and appears to be either seized or cross threaded. I was afraid of breaking the shaft turning too hard. If I cannot get that discconected there, can anyone tell how difficult it may be to disconnect it at another point or what other alternatives i may have?