We lived in Central IL for 18 years on a small hobby farm (15 acres), and I farmed with an 8N, then eventually added an AC 190 loader tractor and replaced that with a NH Boomer 8N when the AC's engine seized.
I had about 11 acres in alfalfa hay, which had to be 'rebooted' every 5 years or so when the weed content got too high. Alfalfa is autotoxic, meaning you can't sow alfalfa right back after plowing, as it won't grow. So I would have one of my "real" farming friends plant corn or beans for a year before going back to alfalfa.
I plowed the field down twice with the 8N and a 2-14 plow, both times after a corn crop. Had to stop often to clear trash out of the plows - the corn stubble plugs it up pretty bad.
The discing pic is after a bean crop - no plowing needed, just discing to break up the surface before drilling.
It's best to plow in the late Autumn/early Winter, then disc in the Spring after the ground has thawed. If you're new to plowing, search the forum for instructions on setting up a moldboard plow - you have to set it up one way for the first row, then angle it for subsequent rows as your right wheels will be down in the furrow. Note - no stabilizer bars when plowing or discing, too.
Also, learn to pick a visual point at the end of the field and drive to it - don't watch the plow or disc, as you'll leave a furrow so crooked a drunken snake couldn't follow it!
I used an old Van Brundt/John Deere drill to seed the alfalfa and oats (for a nurse crop) - I presume you'll use some other means for planting pumpkins.
If you can lay hands on a culti-packer (fluted roller), that's a great tool for improving soil contact with the seeds and knocking down high spots. Otherwise, a drag harrow can work well, too, although you probably don't want to use that on pumpkin seeds.
The area where we lived had a lot of pumpkins grown as there was a processing plant in the area.
So at minimum, you'll want a 2-14 plow and a disc. Search the forum here for "Zane Thing" for a modification to your 9N to add draft control (if I remember right - my 8N already had it ex-factory). That helps a lot when plowing as it automagically keeps the plow depth fairly consistent. Zane passed some years back, but there may be others on the board who can help.
Hope that helps!
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