freightliner fld120 gage lights flickering

So I have been having an issue with my gage lights flickering on me. It started right after the last time I took my dash apart to change a couple air actuators and replace a leaking air fitting. I have tried making sure all the sockets are tight in the holder of the gage and they are. Only other thing I could think of is if there is a cab to dash ground somewhere. Was wondering if anyone knows were the main dash to cab ground wire is. Cant seem to locate it. Or if anyone has any suggestions as to what else could cause this issue. Also if it has any relevance, my radio at the same time has been going in an out, mostly on AM but is affected on FM slightly also. It is not every single one of them but I would say like 80%
Oh and what I should mention also is I have blue leds in them. I put them in about 3 months ago and they seemed to be fine but then started the flickering. I also saw that another guy had a flickering problem with blue. Just not sure why they would be fine for 3 months and then all start doing this. Maybe something with the dimmer?