So some of you have been following my Plan B build, but I thought I would do a separate thread on the engine swap. My swap will need to be California smog legal, and I'm using multiple donors parts from different years for the build. Why the SOHC? I understand this is the first question asked. Simply, because I had a perfectly good complete donor, and the motor only has 103k and runs super smooth. No chain noise. Plus out of the box, it's the same hp as the V8. We're Starting off with a 1991 Mazda Navajo (Explorer Sport). Stock OHV 4.0 Manual Transmission (M5OD-R1) Auto/Electric transfer case (1354) I'm removing all of the wiring, and I do mean all! Everything from taillights to headlights. as well as the fuel tank. The plan is to keep the Navajo dash, and try to get the donor parts to swap in. from cluster to hvac, to even the headlight switch. I'll also try to keep the original steering column. The donor vehicle I'm using is a 2000 Explorer Sport Stock SOHC 4.0 Auto Transmission 4x2 (5R55E) - this will not be used Substitute Donor parts 2008 Ranger FX4 Auto Transmission 4x4 (5R55E) 1994 Explorer Sport Manual Transfer Case (1354) I'll be swapping over the entire wiring harness from the 2000 Sport over to the Navajo, again taillight to headlight. Also the gas tank, cluster, and havc. Since I cut the back roof off the Navajo, I'm not 100% I'll even bother with the A/C, but heater will be important. For the SOHC to fit, I'll need to swap the entire HVAC box off the firewall. Other issues will be the steering, but that shouldn't be to big of a deal, as I try to keep the Navajo column. I'm not sure If I could use the power steering pump off the OHV on the SHOC. this would eliminate figuring out new PS hoses. The break booster and pedal assembly will also be swapped over. All smog will be swapped over and of course, everyone's favorite, as I will retain PATS. Yes PATS in a Navajo. Everything for the most part should just bolt in. As I'm basically just swapping everything over to a newer body.