You're lucky. I believe those particular type of winches were only made for a short time in the 1970s. I searched the internet and asked Lewmar for a schematic, and all I could find were schematics of other designs, and not that particular style. The feature that distinguishes them is that they have six allen screws in the top cap.
I have a similar pair of winches and finally figured out how to dismantle them, at least for the most part. I believe the following instructions will work.
Step 1: Grasp the stripper arm and turn it counterclockwise for about 1/2 turn. (Don't try to remove the stripper arm completely, because you can't at this point. All you're doing now is loosening it, so you can remove it easily later, without having to use a tool. If it's too tight, and won't turn, don't worry. You can use a wrench later to remove it. Just go to Step 2. )
Step 2: Remove the six allen screws from the top cap, and that will enable you to lift off the top cap and the stripper arm beneath it. Next, you'll see a stainless steel disk with the allen screw holes in it. If you were able to loosen it in the manner described in Step 1, above, then you should be able to unscrew it and simply lift it off the shaft. If not, then you can remove it by using a large pipe wrench to turn it counterclockwise. After that disk is removed, you will be able to simply lift off the entire outer shell of the winch, exposing the inner structure of the winch. (Be careful when you lift the outer shell. On your model of the winch, I believe there will be two roller bearing races, and there is a good chance that they will stick to the shell when you lift it off, and then fall to the floor, scattering rollers under the refrigerator and stove. If you lift the shell partially, and then bump it with your hand, that should cause the bearing races to become unstuck.)
Step 3: Carefully lift the two bearing races off the central shaft and set them aside. I believe there will also be a thin separator between them. When the races and separator have been removed, you will see a thin jacket around the center shaft, toward the base of the winch. That jacket doesn't look like it can be removed, but it can. If you can't loosen it by twisting it with your hand, use a pipe wrench to remove it, being careful not to damage it. It shouldn't require much force to remove it. After it is removed, you'll see two small plastic or delrin keys that hold the center spindle in place. As I recall, after removing them, you should be able to lift the center spindle out of the winch. I don't remember for sure, but I might have had to grasp the center spindle with vise grips to break it loose from dried, caked grease that held it.
After you get to this point, you'll be able to figure out, from visual inspection, how to remove some of the other parts. I wasn't able to completely disassemble every part, but when I reached this point, I immersed the entire winch in a bucket of solvent, let it soak overnight, rotated the center spindle occasionally to loosen any grime, and was able to clean everything satisfactorily.
There is another bearing race inside the winch structure, that you can only see from underneath. I wasn't able to remove it completely, and, rather than break something or damaging it trying, I was satisfied to clean it through immersion. There are also gears underneath that I cleaned with a brush and solvent, rotating it to expose all the surfaces.
After cleaning, I lubricated the gears with white lithium grease, and lubricated the pawls with 30 weight motor oil.
I didn't have to replace any parts, but looked for them, just in case, and believe some might still be available, but they'll be very hard to find. If you find a parts source other than pyachts, which I know about, let me know.
I think you'll be able to dismantle your winches from these instructions, but, if you need photos, let me know and I'll try to accommodate.