When fitting a upper and lower is it best to take off of the uppers rear lug or open up the lower receiver?

Can you re-state what you are asking?

I'd rather remove metal from the upper receiver.  But only as a last resort.  If they fit that badly, I'd try to find out which part is out of spec and replace it.

Oohhh i see, you are talking about modifying the upper/lower for a tight fit.

Yes. I'm trying to fit a upper to a lower. The upper fits into the lower with out any side to side play. But the upper doesn't slide to the rear enough for the take down pins to slide in. I've noticed on my Bushy that the rear area where the lug goes has more metal removed.





[img]http://www.harveys-supermarkets.com/graphics/Inside.jpg[/img]
My Bushy doesn't have as much metal where the arrow is pointing. The upper fits fine in my Bushy lower because of this. Which way is right?

Suggest you only take material off the upper. It's an easier part to modify, and probably the cheaper part in case something goes wrong with your mod. But it should only be a matter of removing a small amount of material. If you want to get fancy, use Prussian Blue to identify the area to cut. If not, you can use some of your wife's or gf's nail polish. If you bought the upper recently, I've noticed some of the ones new on the market are a little tighter than the older ones. Good luck.