Keep OEM Bilstein shock but lift using a longer spring?

the coil spring we sell is maybe 3/4" longer than stock with a slightly higher spring rate over stock. it does not cause top out and the ride isn't much more firm than the stock coils. i was hesitant to change the red Bils and our ADO coils out for the fox 2.5 i have on the truck now because i enjoyed the ride quality.

We pair our coils with 5100s in the other make/models that they are available for. the 5100s just released for the 4g tacos, but we feel the red Bils are a better shock because of the added mini reservoirs. if you have a base model truck, we offer customers both the 5100s or we have the factory red Bils in stock also.

 

so the eibach pro-truck front shocks, lift 0" at lowest setting. so i assume perch height is in same location as stock. eibach front pro-truck springs lift 1.8" with no adj on the shock.

So that being said i would feel very confident saying that you can use the eibach spring on the trd bilsteins for a lift. i got a solid 1.8" out of my 4wd sport with the shocks at zero lift, all spring.

dont know if this helps , but it is what i have observed