With the note I haven't tested this, this should work. The position of the ldr changed because there is a logical inversion caused when the second transistor is added. When its dark the ldr will be high resistance, and Q1 will be off. Q2 has around 9 ma flowing in to its base and is thus hard on lighting the leds (you need to watch the collector current rating of Q2 but for 6 leds I expect it will be OK). When there is light the ldr is lowish resistance (10K or so I think) and base current flows in Q1 turning it on (this part works in your current circuit and thus should work here to). That robs the base current from Q2 which shuts off and the leds go out . You could use a higher resistance for r1 to reduce current draw slightly but it isn't likely to be much against what the leds draw a 10k resistor would reduce the base current to around a milliamp which should still provide enough drive for the leds (if not
reduce the value of r1 til they light correctly).
Peter Van Epp