First with the Peptides.
GHRP-6 is not the best choice if you are trying to cut. It can cause some pretty intense hunger pains, which usually end up in a person destroying there kitchen. This can be beneficial to some while cutting, but at 20% body fat, I would opt for another GHRP.. either GHRP-2 or Ipam.
Now, to get the most out of this, you will want to stack your GHRP with CJC-1295.. either with or without DAC.
For your goals, I would start with CJC-1295 w/Dac, and add in GHRP-2 and IPAM. The CJC-1295 DAC will cause a GH bleed, which is great for losing fat. The body recomp from this peptide can be amazing.
I would run it CJC-1295 w/DAC at 2-5mg week, dosed once per week before bed. Then while you are on that, it would be beneficial to add in GHRP-2 and Ipam to get a strong pulse of GH during the day. A typical protocol would be 100-200mcg GHRP-2, 2-3 times per day. You just pin this subq in your stomach. You will want to wait about 30 minutes after pinning to eat anything, because food/insulin will blunt the GH release. Typical times to dose GHRP-2 would be first thing in the AM, followed by 30-45 minutes of fasted cardio. Then again Post workout. You last dose being taken directly before bed. You can use this as many times per day as you would like.. just make sure there is 2-3 hours between each shot, and you wait 30 minutes after shot to eat. I would suggest switching from GHRP-2 to Ipam for your dosage before bed. The Ipam is active much longer than GHRP-2, so the GH pulse while you are sleeping is amazing. The sleep is also amazing.
I would run this stack for 8 weeks, and then after the 8 week mark.. switch from CJC-1295 w/dac to CJC-1295 w/o Dac.. also known as Mod-GRF. Just add in 100mcg to injection of the of the GHRP-2 and Ipam. You can run this for an extended period of time, and all the way through PCT and beyond. The increased GH is great for cutting fat and leaning out.
Now, based on a lot of research I have done.. It seems that the fat loss from Cardarine/GW-50 is blown out of proportion. People rave about the increased endurance it provides, but say that fat loss leaves a lot to be desired. Basically, the users didn't see any added fat loss from your diet and working out alone. I personally think that is is something that needs to be ran 6+ months to experience significant weight loss, so your 3 weeks on/of protocol would not be to wise in my opinion. GW-50 is suppose to shift your metabolism from burning the food you eat as fuel, to burning stored fat. It is also supposed to prevent access food from being stored as fat. I think this shift will take a long time to fully happen, so running it for short periods of time would not be ideal. Now all of that said, GW-50 is different from a lot of weight loss/fat loss aids.. in that it actually increases nitrogen retention.. so it is not catabolic. Running this on Cycle, in PCT, and after could have some pretty good benefits. Typical dosing is 10-20mg/day, either dosed once in the AM, or taken 60 minutes before workout.
Now about your cycle..
Why on earth are you bulking at 20% body fat? I am a big guy, typically stay around 15% body fat, so you cycling at 20% body fat doesn't bother me. But, trying to bulk.. even a lean bulk, not a good idea in my opinion.
As far as the Clen and T3. In my opinion, I would save it. At your current stats, I think you will be able to shed plenty of fat with just diet and training. The GH peptides would be a better, and more sustainable fat loss aid than Clen and T3. That said.. I know you will most likely still use them. So just keep it simple. I'd keep your Clen dosage between 60-80mcg/day, and run it 2 weeks on/off. Would be a good idea to use Taurine with Clen because of the cramps. As far as T3, I would keep your dosage between 50-75mcg/day, preferably 50mcg. Any higher, and you are looking at burning muscle along with fat. I would run the T3 for 6 weeks, and stop it at least 2 weeks before PCT. Adding in a thyroid support supplement at this time would be a good idea to help get the thyroid back function asap, so you avoid rebound from fat loss.
As far as your Winny dilemma, I would just stop the orals when you run out.
Sorry for the long post, hopefully this will help you a bit.
Best of Luck mate.