Yes, the 4.2124 is correct except for the front which needs the 3.2125 kit. The front also needs the existing spring eye bushing sleeve (shell) reused.
I didn't include the "R" at the end because supposedly the black carbon coloring in the black version instead of red, will reduce squeaking.
You might want to check ebay for the ES or Prothane version (might be part # 6-1019), they were much cheaper when I bought them there. They were old stock but urethane doesn't age as much as rubber does. Edit: I just checked and didn't see any on ebay deeply discounted like I did back when I got mine.
Getting into specifics, the 4.2124 was meant for a 91-94 model year, which shares the same rear bushings but the front bushings for '91-'94 are RB-159 with OD 1-5/8" and ID 9/16", while the 95-01 Explorers use RB-237 front bushing which is 1-7/8" OD and 14mm ID.
If you are only doing the spring bushings, then you don't necessarily need the entire 4.2124 kit, can just get a pair of ES 2086 for the rear, but it might not be much if any cheaper depending on the kit price, and I don't recall if 2086 includes sleeves. The ES 4.2124 kit includes:
6 x metal sleeves - all the same
2 x 2089 Upper Shackle - Frame bushings
2 x 2090 Upper Shackle - Frame bushing, thrust washers
4 x 2061 Rear spring, front eye bushings
4 x 2086 Rear spring, rear eye bushings
