There isn't any "drilling out" a needle and seat. Their a matched set. The taper on the needle matches the taper in the seat. Most people have been going to the bigger needle/seat, as a mod when going "pumpless".
You'll want to check the float level. Yamaha revised it, to match the 04 and later bikes. If it is still set to the original 99-01 setting, you'll want to raise it. Its a big change.
The Barons kit will give you a starting point, based on your mods. They'll probably suggest a 172.5 main
, stock pilot
(35), and the clip in the fourth from the blunt end of the needle. PMS
screwed out about 2 to 2.5 turns from lightly seated(to start with).
If you haven't already drilled the plug over the PMS screw, there will be instructions, bit, and a sheet metal screw to pull the plug, in the kit. I would suggest getting the Baron's adjustable PMS needle(or something similar), to make fine tuning easier. It doesn't come in the Jet kit.
Read everything you can, in the Tech Articles, and doing searches on the forum regarding jetting, while your waiting for jet kit. Check for leaks around the intake manifold, and make sure that the "Coasting Enricher" cover on the side of the carb
is in good shape(not cracked), and the plug on top of the manifold where the AIS
vacuum line was installed is sealed up good as well.