How to take apart rear bottom/bench seat cloth upholstery? Need DEEP DEEP cleaning

To make a long story short, I accidently had a bottle of gear oil (which smells horrible!) on the passenger side of Tacoma and I didn't notice that it was leaking until a couple days later (smell). I'd say 1/3-1/2 quart leaked onto the bench. Of course it soaked it up like a sponge.

I took it out of the truck and literally dumped a full bottle of dawn on the seat and let it soak all night. The next day I tried to soak/rinse in the bathtub with hot water, with several times rinsing and "wringing out" (standing in different areas, several times). I am sure I got a lot of it out, but anyone that has dealt with gear oil, knows how bad it smells (contains sulfer). It is now in my walk in shower and have since used 2L of Superclean cleaner at 5:1 ratio, let sit over night, rinsed with hot water and "wrung out" (stepped on) several times and then I used another type of all purpose cleaner 2L and did the same process.

While the smell is better, it still isn't gone, and i havent dried it all the way yet either, so I am not sure if I have ALL of the oily residue out either. I am thinking that maybe I should take the whole cover off and have better access to the foam. I can find a DIY on the front seats (since some cover them or reupholster them more often than the rears.

I cant seem to find, but is there a DIY on how to remove the rear cloth upholstery? Any other tips regarding this type of situation?

 

Just burn the bench, install a platform instead, that part of your life is over now

 

Gear oil is some nasty shit! I'm thinking you will be replacing that thing. Start calling salvage yards.