Mine were really tight on my L3800 as well. It was pretty frustrating at first until I took a dremel to the folding part of the ROPS and reamed it out a bit. Now the bolts go in pretty easy. Must be a pretty common issue with that tractor.
I was dead set on the JD3038E at first until I looked at the Kubota L3800. I also did lots of research and several folks had issues on the JD with the front axle seals leaking. The Kubota in my opinion is a lot more tractor. I looked at most all of the big brands and I brought home the L3800 and...
I just bought a brand new L3800 tractor last week and my 3pt hitch it pretty smooth. Also you should have had them space out your back wheels. Makes it much more stable and you don't need spacers with the AG tires. You will love this tractor!