Do you have a Taco? They would certainly fit. Im running Taco bilstein 5100s with my 99 coils right now. 1st gen Taco and 3rd gen 4runner front suspension is interchangeable. How they would ride, who knows. I have been doing a ton of research on oem taco and 4runner coils lately, and Im pretty sure the 4runner coils are actually stiffer than the Taco coils. 4runner stock coils being 500lb rate, and Tacos being like 450. At least thats what moogs oe replacement coils for the taco are
I can say this . . . nissanh here on the forum installed a set of Taco TRD coils/shocks from an 02 Tacoma, and he said the ride is far better than 99 coils. I am planning on installing Taco progressive coils on my 4runner as well. So going from Taco suspension to 4runner suspension is going in the wrong direction, unless you are looking for a stiffer ride.