I've almost completely replaced the bulbs on my 2005 Hilux with LEDs. All that remains are the headlamps which don't have LED replacements and the signal/parking lights in the front bull bar. All the bulbs and replacement flasher relay was purchased from Hong Kong, off ebay.
Here's a quick summary of the type of bulbs used. Sorry don't have pics at the moment.
Cabin Dome Lamp-31mm 6 x LED (Warm White) Festoon Bulb x 1
Map Lights-Mini Bayonet T4W 5 LED (White) Bulbs x 2 (Because of the orientation of the socket, a forward firing LED will shine forward, so little light will be projected downwards where you want it. Look for LED bulbs which shine perpendicular to the bayonet lugs or with multiple LEDs)
Alpha Canopy Dome Lamp-36mm Single high power (white) Festoon Bulb x 2 (I should have gone with the multi LED type which I think has better spread)
Rear Brake-Bayonet 1157 30 x LED (Red) Stop/Tail Bulb x 2
Front & Rear Signal-Bayonet 1156 30 x LED (Amber) Turn Bulb x 2
Rear Reverse Light-Bayonet 1156 13 x 1 Watt High Power LED(White) Stop/Tail Bulbs x 2 (You can also use this for the front and rear signal lights since the lenses are amber coloured) This bulb uses 13 x 1 watt LED instead of 30 smaller ones like the ones above.
These LED bulbs use the same base:
Front Low Running Lights-194 T10 W5W 1Watt High Power LED (Xenon White) Wedge Bulb x 2
Side Signal-194 T10 W5W 6 LED (Amber) Wedge Bulb x 2 (Make sure you don't get bulbs which are too tall, these are 22 mm tall)
Rear License Plate Lamp-194 T10 W5W Inverted LED (White) Wedge Bulbs x 2 (Make sure you don't get bulbs which are too tall)
Third Brake Light - Haven't figured out how to open this one up.
After I fitted the LEDs, the left signal was hyperflashing due to the lower electrical loads of the LEDs. I also ordered a replacement flasher unit but I wasn't sure how many I needed since I couldn't find the thing. I poked around the fuse box in the engine bay, behind the glove box and under the steering column for several days and I still couldn't find it.
Eventually, I turned the hazard lights on and tried listening for it. I narrowed down my search to under the dash near the steering column and found it by feeling for the clicking from the flashes. The darn thing is attached to the cross bar under the dashboard. Not exactly the most convenient place. I didn't want to bother with dismantling the dash, so I reached in by lying on the floor in front of the drivers seat and reached in. I disconnected the cable from the original flasher (there's only 1) and connected the new one. The old one is still there and the new one is hanging loose at the moment. I'll zip tie it to something later.