No. The springs sit under the frame on the Explorer, so the perches are the same width apart. You can use an "axle flip kit" to put the spring perches on top, or just have a new set welded on top. I'm a fabricator, so I just plan on welding my perches on top. They line up perfectly with the existing ones however, so a flip kit will let you do it without welding.
The disk swap is basically no work, just bolt up the axle at the flex line and it's fine. The bias is acceptable when switching from drums, so you don't need to worry about that, but you do need the explorer e-brake cables.
The explorer axle is spring under, so the factory leafs have a bigger arch to them, this is what gives you the lift. Internet lore says the Sport Trac leafs sit a little taller than the regular Explorer ones, but I don't have any hard evidence to support or deny that. If you keep your longer shackles, and throw an add-a-leaf (I would recommend cutting down your Ranger main leaf and using it as the longest AAL you can install), you should gain the amount of height you're looking for without a block. You'll essentially just be adding the 2" of lift the Explorer pack gives you on top of your AAL and shackle.
Spacers add incredible amounts of stress to the wheel studs and bearings, and they need to be retorqued regularly. Especially if you play offroad. They're cheaper and marginally easier than an axle swap, but an axle swap is not out of your territory if you've installed a suspension lift before. Better shocks will help with the ride, but if you're over sprung for the weight you've got back there, the only thing that will fix it is taking out leafs. You could spring for a Deaver pack ($600ish), or build a bastard pack with XJ, Dakota, F150 and Explorers as candidates for leaf donation. I had considered doing a Skyjacker Softride 6" pack, with the Explorer axle left spring under, and lift shackles, which would theoretically put me about 3-4" over stock height, however I don't intend to keep my Ranger for more than another year or two (growing family), so I dropped that idea in favour of keeping it simple. I don't like tall trucks, so the 2" or so that the Explorer leafs will give me is just right, and will let me ditch my factory block. Probably install a set of Timbren bumps to round out the package. FWIW these trucks will take 32" tires without any modifications and not rub anywhere. Lift is largely aesthetic beyond 2-3" IMO.
