Oh I see now. Taurus uses same engine. Why did you have to swap heads? Only ones from mazda/Ranger fit under the hood or...
And a "302", that's quite an upgrade. So that's complete long block and tranny right? How will it fit in the engine bay? What kind of mods needed? They make adapters or something?
The Taurus and Ranger/B-Series have opposite coolant flow direction in the cylinder heads. Thus, Taurus heads don't work on Rangers and the reverse is also true. There were also some differences in the oil pan, the shape of the oil pickup tube, harmonic balancer, etc. The main thing is that a Vulcan 3.0L in a Taurus is made to sit transverse, or sideways in the engine bay with respect to the front and back of the vehicle. Our trucks that have the Vulcan 3.0L have it sit longitudinally, or in line with the front and back of vehicle. Due to the differences in placement some stuff has to be swapped to convert the block from one setup to the other.
As for the 302 swap I'm preparing for, I did manage to buy a longblock that was almost fully dressed, meaning it has the harness and all accessories, brackets, bolts, etc. It also came with an automatic trans but I want to pair it with a M5R2 manual from a F-150 so I didn't purchase the trans, only the engine. As to what modifications that are needed that is largely going to depend on what you are coming from and where you are going. My swap will be on the more challenging side because I want to maintain EFI and there's 6 years of difference between the donor vehicle (2000 Explorer) and the recipient (1994 B3000). One of the biggest challenges is that my truck was the final year for OBD1 while the donor is OBD2. This means you have to use the donor ECU and harness. The donor ECU was designed to seat around the center of the SUV at the top of the firewall, while the ECU in my truck sites near the driver fender on the firewall. This means the harness needs to be extended to reach. Lots of issues like this. I have a build thread in the V8 Swap section of the forum if you want to follow the progress(or lack thereof) that I've made to date.
Depending on which model years are involved there are full conversion kits available that will take care of about 90% of the issues you'll run into. The nicer the kit, the more spendy it is. There is a TON of information floating around on the interwebs, much of it on these forum boards on how to do a V8 swap. I cannot stress enough that there are tons of combinations of donor and recepeient so you'll have to do your homework for the things that apply to your particular use case.