First off, LED's are polarity specific can be installed only one way. If the circuit was working before with regular lights, then you perhaps you put the tach and speedo LED's in backwards. Try flipping them in their sockets.

The lights are wired in parallel, BUT, the way the circuit is routed through the flex cable, circuit 1 (which is dash illumination) goes first to the tach, next to the idiot light illumination, then to the speedo, and finally to the clock. If there's any problem in the circuits, it might be in the grounds (circuit 3, which on the "wings" that run to the tach and speedo is the center copper strip.) 

i agree about LED's in the dash. Though they're colder light, they make the gauges appear very sharp, when they're all working.

Good luck,

Jarrett