How would you clean a hot tub cover?

I have a hot tub on my deck. The cover is in pretty bad shape. It is grey vinyl. I have many trees in my back yard and there is sap all over the cover. I use the conventional cleaners from the hot tub store, but they are not strong enough.

So, I`m thinking, "I have a Porter Cable and a hell of a lot of detailing supplies - I can handle this." But I don`t know what to use. Here is what is in my arsenal:

PC w/ Lake Country Cutting, Polishing, and Finishing 7.5" Pads
Klasse AIO, SG
Poorboys PP, PwC, SSR2.5, SSR1, EX, EX-P, Spray&Wipe
Stoners Bug&Tar Remover, Carpet Cleaner, InvisGlass
1z Cockpit Premium, Vinyl/Rubber Protectant, Leather Treatment
P21s Wheel Cleaner

Any ideas on attack? If I screw this up, its no big loss. I would have to buy a new cover anyways. I`d rather save the $$ and give this a try. The 1z Vinyl/Rubber Protectant did nothing in my test area.

I`ll post some before/after pics once I have a Gameplan and try this out.

I would S&W with a stiff brush, if you can get meguiars #39 locally that maybe a good option.

A friend of mine(00Ranger) uses S&W to clean his outdoor furniture.

As for the hot tub itself, PP hands down. It will clean anything.

Yeah, I have been reading these posts about how PP cleans everything, so I figured I`d give it a shot on the vinyl cover. Cutting Pad at 5.5, right?

Seriously, I have no intention of ruining any PC pads on a vinyl cover. This will be done by hand.

First, I`ll try Spray and Wipe, followed by PP.

If successful, I`ll seal with ?? EX-P?

On the vinyl, if it`s a soft cover Spray and Wipe followed by Trim Restorer since it sits outside, if it`s a hard cover then I`d use the combo you just described:)

If all else fails try a vinyl siding house wash. It usually has chemicals in it to kill the mold and mildew.
Or, mix up a mixture of dishwashing soap and bleach (it too will kill the mildew)
Follow imediately after it dries with a protectant.

Forgot,
I cleaned mine with the vinyl siding wash with no problems.