Congrats on your new lo! Looks like you are doing a great job! {{{HUGS}}} to you! Take a deep breath, and lets look at your day.
I'll make some suggestions, but just remember that they are suggestions and might not work, and might not suit your family.
I don't think he necessarily has his days and nights mixed up, which is usually solved by 8 weeks anyway, so his night wakings must be due to something else. You said that you thought babies should only have 4.5 hrs of day sleep, but just remember that every baby is extremely different. If you are trying to stick more closely to a 3 hr routine, then I would try to wake him before he is due for a feed at approximately 3 hrs. If he seems very tired, give him a few more minutes, but try not to let him sleep more than 2.5 hrs at a time. Doing so could possibly rob night time sleep.
As for consolidating the cluster feeds, you could try a feeding routine such as: 7am, 10am, 1pm, 4pm, 7pm, then bed, and df at 10pm if you like. If you think the df is disrupting his night sleep, you do not have to give it. It is merely a tool with the potential of ending night feeds. It is common to have night feeds for a bit longer, especially when bfing I believe. IF you are more comfortable with no df and letting him wake when he's hungry, then you should do that.
Remember, you do not have to "go by the book." You should adjust things to your baby's needs. Sometimes I think we get too caught up in what "should" be and ignore what is, and "what is" is what we have to work with.
HTH, keep up posted.