Its been a while since I have done my detailed writeups, so here is one detail session for my tyres. My tyres haven't really been getting a lot of attention for the past few months. I have been washing my car regularly but while doing that the tyres have only been getting enough attention that the visible dirt is removed from them using brush and shampoo/surf solution. Also, I have been putting Meguiars Endurance gel almost about every month, so it was about time I cleaned them thoroughly to get rid of any embedded dirt and older layers of the endurance gel.
Products used:
1. Tyre cleaning nylon brush with hard bristles
2. Foam sponge
3. 3M APC (diluted 1:4)
4. Surf solution (I could have used shampoo, but was really after deep cleaning tyres).
Procedure:
I rinsed the tyres with water and figured the older layer of Meguiars endurance gel was still on (since it was repelling water) but the dirt accumulation had turned the tyre to somewhat dark brown. Here is how the tyres looked in the start:

I then sprayed the 3m APC (1:4) on the tyres and rims, let it dwell for a minute and then washed the rims area and then used the surf solution with a sponge and rubbed it with the brush. Here is how the tyre looked during wash (just when it was rinsed, its currently wet with water). The water now sticks to the rubber and stays there, sort of confirming prior layers of endurance gel are gone. Also, the rims sparkle MashAllah.

and so is the dirt, finger swipe test (nothing sticking, tyres seem squeaky clean):

Now, applied the Meguiars tyre endurance gel and here is a 50/50 shot:

Here is a before and after shot of the same tyre area:

and here is how they finally looked:

Thanks. Comments and feedback is welcomed.