I've been busy here lately so forgive me on the late reply.
My side gig is running my own reel repair/tune/clean business....so I can point you in the right direction. What I do and what I recommend doing are usually two different things....as I do have a lot of equipment and tools to clean reels, I realize not everyone has this stuff or gets paid to service reels so...there ya go.
For the DIY'er at home:
Once a year at a minimum clean your reels using a simular method:
If you feel comfortable opening them up, lay all pieces out in the order they were removed. The DIY'er can get away with stopping at removing the gears. You don't have to remove the worm gear parts or clutch parts (pieces that are held in with springs and screws in between the pinion gear and frame. The parts you removed, wipe clean with a rag. You should have two brass gears, drag washers, yoke (piece that pinion gear and 2 springs ride on). Again clean all parts you remove with a degreaser. You can use simple green or aerosol spray degreaser. Aerosol spray degreaser would be the easiest thing to clean the rest of the reel because you will have some pressure to the spray to force the dirt and grime out. Spray everything and then remove the residue with water. Let dry completely. While frame is drying, remove the three bearings that the spool rides on. Usually one on each side of the spool and one in the middle. If the middle bearing is behind a pin on the spool you will need a special tool to remove the pin....Put bearings in small jar and fill with a degreaser. Let bearings soak....go get an electric tooth brush or other vibrating device you may have in the house and hold to the bottom of the jar to help bearings get flushed out (mimics the effect of an ultra sonic cleaner). Then discard the solutions and repeat with either lighter fluid, finger nail polish remover, or acetone. After a few mins take bearings out to dry.
At this point everything should be dry.
Grease gears (not oil), and light coat of grease where you can see wear marks between the frame and reel parts. Assemble gears and drag washers in same order applying very light coats of grease to the washers (if you can leave a visible fingerprint in the grease, its too heavy). Next time you order from tackle warehouse, buy Shimano drag grease for your reels. One ounce will last you years otherwise use what you have on hand.
Apply one drop of oil to the bearings, one drop to each side of the spool shafts, one drop on the disk behind the bearing spool ends, one drop on the brake system, and a few drops on the anti reverse bearing in the handle, few drops in the worm gear and maybe even a few to the handle.......thats it.
A DIY'er can get away by owning one oil and one grease product. Oil here is much more important than the grease....so I recommend ReelX oil....($6 at Tackle Warehouse).
If you wanted to get more in depth, you first need to purchase a ultra sonic cleaner because without it, you will never get anything perfectly clean.
What do you all do for your reels to start the Spring off right?
In the past, I've pretty much fished all year, but gave them a good cleaning and tune before Spring. Last few years, the reels have stayed unused for months.
I've stripped all the reels of line, broken them down and degreased them. Then I apply grease to the parts that rub and light oil to the gears, etc. Follow that up by cleaning the bodies and applying some non-greasy protectant.
That's certainly not a professional regime, but it's worked well for a few years.
Any body have a solid reel maintenance regime?