Hi, there. Glad to have you with us.
Are you using the slowest flow nipple/teat with the bottle? If so, you might want to change brands. Not only do you not want it to flow too fast, but I think babies also need the suckling time. At six weeks, I think feeding him at 2.5 hours is fine. However, he could begin to make the shift within the next few weeks to 2.75-3 hrs. Was he a low birthweight baby?
Do you give him a paci? My dd wanted to nurse forever, even after she emptied the breast. She just wanted to suckle, so I would pull her off and slip the paci in and she was fine. I also sat her upright in a bouncy chair for 15-20 mins after a feeding to help with gas and digestion. I also used gas drops with every feed, breast and bottle, and still put them in her bottles now.
As for getting him on EASY, it's going to take some time. It doesn't happen in a few days, especially at his age. I believe that things tend to fall into place closer to 3 months b/c newborns change so much and so often. And the df might not happen right away either, but you should certainly give it another try. I had to completely wake my dd for the df. And she'd eat and go back to sleep.
What time do you try to start your day? If you can give me a typical day, I might be able to make some suggestions.