I'm assembling my 80% lower and there seems to be an issue with the fit of the trigger.
When 1st assembled nothing worked, the disconnector  would not release, the trigger would +not engage, and the safety selector could not be installed.
When the trigger is installed the rear portion is not low enough to install the safety, this is where I believe all the problems start, not having the safety in place allows the rear of the trigger assembly to rise higher than it would with the safety in-place.
I was going to start modification to the bottom rear of the trigger (grind) to allow it to sit lower and clear the safety selector hole, then I might have a better idea where to go next.
I'm a little apprehensive about removing material from the top rear of the trigger that it might affect safety engagement, how much material can safely be removed from this area? (http://junkyardgenius.com/firearms/ar-15/ar08.html)
Has anyone else experienced this problem?

Don"t do anything to your trigger. Check the depth of your fire control pocket.

Don"t do anything to your trigger. Check the depth of your fire control pocket.

I was going to note that, it's 1.255, drawings show 1.249

Are the springs on correctly. How does the trigger fit and feel without the hammer. I had a simular problem as i had milled the trigger hole wrong.

It's happened to me too.

You need to remove another 2mm's of metal on the floor of your receiver.

G.

Dont remove anything. If your at 1.255 your already beyond spec.  Spec is 1.249. Check the hole in the bottom of fire control group.

Do not start filing on anything in the FCG, you will render it useless and then have to buy another one, something is off in the safety selector hole, you need to possibly work on the safety hole a bit to get the safety to fit correctly, then start looking at the pocket depth, make sure all of your springs are in the correct orientation, double and triple check things.  Remeasure you pocket depth, if you are at 1.255 you are to deep, but it should not cause a problem.

Go through the steps and don't get impatient!  But again, do NOT start filing on the fire control group.

Is this your first 80% build?

2nd receiver, the 1st went together with out any problems, I used the same jig and same receivers (Daytona Tactical).
I mocked everything up with out springs, there is still problems. The trigger on its pin no springs is still too high to get the safety in.
There is slight contact at the front of the trigger in the trigger relief hole, but that does not limit the rear of the trigger assembly to bottom out on the receiver floor, so I either have to lower the rear of the receiver or remove a bit of material from the trigger. I really don't see too much harm in removing material from this area of the trigger as it really doesn't do much.

Check the length of the slot for your trigger.

If the front end is too far to the rear, the trigger will not swing far enough forward and leave the rear end of the trigger in the air, so to speak, blocking the safety.

It sounds like you are plenty deep (and then some) in regards to the fire control pocket.

- Chris

I got it,I verified if there was contact at the rear of the trigger to the floor and there wasn't, so I turned my attention to the trigger interference as mentioned by a few of you, filed the trigger slot till I had no contact, mocked everything up and it seemed fine, I installed all springs and safety selector and all is working as it should.
Thank you all for your inputs and suggestions.

Same thing happened to me. The router plate on my easy jig wasnt marked front back. I had to figure that out on my own. My trigger hole is a little longer now but it still looks good.