That will work! That is how I use mine. You don't have to have the fertilizer box.....it's nice to have but it isn't required. As long as the planting mechanism works your golden. Maybe you can get it cheap......I got mine when a guy I knew was cleaning out an old building and he just wanted the room. He was going to scrap it.....I about had a kitten! I paid him $50 for the planter and a bucket full of the planting plates and the original manual for it. It looks like hammered crap, but it still works.Your answer is what I've been trying to tell myself for a while now. All the farming in this area has dried up so that's not an option but, a fiend has an old 2 row that I can use just doesn't have a fertilizer box.
IF I plow - I plow first, run the disc a pass and then apply my base fertilizer via a conical spreader. I then disc that in and then plant. I then follow up after germination with a dose of gly when needed and then a "booster" application or urea (again with the cone spreader).
IF I use a tiller - I simply apply my base fertilizer dose and then till everything it and then plant. I follow up with gly and the "booster" dose as described above.
I prefer to work as much fertilizer into the soil as possible to prevent any running off in a rain storm.
I apply the gly and booster dose when the weeds start to challenge the corn - my tractor doesn't have great ground clearance so I have to ensure I do it early so I am not damaging the corn in the process. You can also apply all your fertilizer in the initial dose it you want, but the weeds that germinate will use some of that fertilizer as well. I don't pretend to be producing at production farming rates. Mine is set at 30" row width and I plant at 30,000 to 35,000 seed density per acre. I tend to shoot for 100 to 150 bushel of corn per acre and in my area the "rule of thumb" is that relates to applying your base soil fertilizers based on soil test and then an additional pound of N per bushel of grain corn you want to produce per acre. Just to be clear - if I want 100 bushel of corn I apply 100 Lbs of N per acre above the base soil needs. The easiest, safest way for me to do that is to apply Urea (46-0-0) so it's roughly 50% actual nitrogen. So to reach that 100 bushel mark I would apply roughly 200 lbs of Urea per acre.
I'm no corn expert by any means, and soil conditions and the like make a huge difference. I will also tell you to save your absolute best soil for corn. Corn is very hard on soil and very demanding of it. let me know if I can help in any way.
Just as a reference I use an old For 309 plate planter. It almost looks like something that should be pulled by a horse! There are far better planters out there, but I use what I have.