Did you test them before putting them in to check for brightness? In my VK the standard lights are dull as well, so im also going to have a guess at it could be the facia that could also be the problem? If none of the above, check that you wired the LEDS correctly, got the right voltage through them.
i have ordered leds from hong kong,there 4mm longer that standard globes so there closer to the dash and they are completly covered in leds so ill try them there like $10 for 4,yea was all working but i thought the leds were just dull in day i didnt test them at night cause i was in a rush to reasemble the dash
I brightened my dull VH dash up with white T5 LED's from the LED shop.http://www.ledshoponline.com/automot...board_bulb.htm
I used the 3X3050 T5's. They have 3 LED's on the one stick. Fit straight into the standard wedge socket, and I would say it has at least doubled the brightness of my dash and it's now a white light instead of dull orange
from memory the VK uses the larger T10 type socket, which gives you a bit better range to choose from. But I'm very impressed with the ones I bought. I'm slowly replacing all the dash bulbs including the clock backlight, switches etc.
Also if its any help, I once redid all the dash switches and speed alert LEDs in the VS. $2 a LED for some super bright red or blue ones. Chucked in a resistor so we didnt blob the LEDs Mind you, you should not use Super brights. At night its absolutely blinding. So if your pretty good with a soldiering iron you could give that a go.
Ill be buying another dash soon to try some ideas and getting better lighting and do up a DIY eventually. But im just running off some ideas for you now.