It is hard to get an accurate measurement of the TIM pad thickness on my EVGA RTX 3090 FTW3 Ultra when I removed the heat sink assembly for the purposes of re-applying the GPU TIM.
The Memory TIM pads are of a very soft consistency and can be broken/stretched or marred when removing if you just try and pull them off.
As shown in the photos, I managed to lift them off with a wooden flat stick, But not without causing damage to the soft putty like TIM.
As far as that super soft putty that was "pasted" between and on the VRM's, I just cleaned all that off with Isopropyl alcohol and used some 1mm TIM strips as a temporary "fix" until I run some VRM temperature checks and compare it to my SECOND FTW3 Ultra that I have not disassembled yet.
The photo of the back of the PCB with the Metal "heat sink" removed shows the memory TIM after I removed it with little damage to them because I did not try and remove them from the chips as I did on the front PCB components.