I have a brand new set of Tokico blue gas shocks and struts from my 2004 GT that i never installed..I know the struts wont fit but i want to mount the shocks on the rear my 2012 GT 5.0. I put the Tokico's along side of a spare set of stock shocks from my 2010 GT from when i replaced them with Qa1 shocks. When i look at them side by side they look identical to 1 another. The stock shocks are gas pressured as well but i can compress them easily, not the case with the takico's. So can use them?

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Looking at your photographs, the shock on the right looks longer. The chassis of each car is so different, it would seem that just the damping characteristics alone would preclude matching them with the springs of the S197 platform. I believe you would need to reference the Tokico specifications by comparing the part numbers for each of those year models.