Additional modifications required:
The KA is not a *direct* fit into the 720 as I'm sure many other people have figured out - yes, it bolts to the transmission but your oil pan will require major modification to work and this will affect other things on the truck itself.
This section will highlight what those additional modifications will be and how to best ensure their proper application to best prepare for your swap.
The Oil pan as we know won't work - both due to the cross-member and steering linkage and due to the Z24 oil pan not being long enough for the block you will require the D21 Oil pan as well as your KA24DE oil pan. The other option is simply removing your cross member, however this is not recommended.
Start by ensuring that both your oil pans are clean of any residual oil or debris - this will include both the inside and outside - I recommend using a wash basin and wipe clean with shop towels/rags.
Start with your KA24DE oil pan - you're going to want to cut a straight line 1/2in above the baffle - this should result in you being left with the part which will eventually bolt to the block with some lip to it.
Next, on your D21 oil pan - do the same however measure 1 1/2in on the baffle and make the same cut all the way around.
On the D21 oil pan the lower portion will not have enough height to clear your new rear sump setup - begin by cutting directly where the sump of the oil pan meets the lower portion so you're left with a large, rectangular shape open.
Make the same cut on the KA24DE oil pan.
Now you should have 3 pieces that we're going to need to all join together.
Begin with welding the KA24DE baffle to the D21 oil pan that has the sump part still attached - Make sure your placement is correct to ensure this will be a rear sump setup to clear the cross member. Only weld the outside of the pan itself, the inside will not require it and doing so will lead to problems when you make up your rear sump.
Now you can place the oil pan on the block itself to see how it's going to look for fitment.
Ensure your pan is clear of any debris from welding/grinding prior to any fitment to the block itself - you can wash it, or blow it out with compressed air.
At this time you will want to begin seeing how you're going to create your rear sump to ensure you have enough height when you weld the final piece to the oil pan.
Begin by taking your old KA24DE oil sump and cut off the pipe connecting to the oil pick-up leaving about 1in of pipe to work with.
On the crank girdle you will notice further down there is a bolt hole where it will now connect to for your rear sump - connect it to this for now.
Where your previous sump connected to the oil pump cut off the pipe leaving approx. 1/4-1/2in of pipe remaining - cut at a 30-40° angle towards the rear.
Next you're going to want the same size steel pipe (do not use the old EGR pipe, there's too much carbon) and begin reviewing how you're going to join the two pieces - I recommend using the acetylene torch with some wire much the same way you'd use a soldering gun.
Upon each weld you make on the rear sump - air cool for 20-30sec then dunk in water to retain steel strength.
Once fully welded up and keeping as low as possible for the oil pan clearance remove your new rear sump and check for vacuum to ensure there are no leaks.
Oil Pan pt.2
Now that your rear sump is finished have it bolted to the block and place your new oil pan over top as it would when fully finished.
You can now see how you're going to weld on the final piece to ensure you have a fully operational oil pan - you can weld it either as a full piece or cut into 2 pieces length-wise to achieve this.
Check for leaks with a bit of gasoline in the pan - once confirmed, clean the pan once more and attach to your block.
Photos coming soon.
The engine mounts I used, I purchased from ]2eDeYe and was very pleased with the overall build quality, however, like everything in this swap it will require some modification to work as well.
The passenger side mount requires no modification and can be left alone.
The drivers side mount does require some slight modification to work.
Begin with bolting your mount to the block itself - tighten all the bolts to ensure the mount isn't going to move while you're working on it.
Using an acetylene torch heat both sides of the mount 1/2 down until it begins to glow, and then hit with a hammer until the lower portion shifts 1/2-1in towards the front of the block.
Unbolt with a socket wrench with extension (it will be still hot)
Grab with a pair of pliers and dunk in water to ensure the structure of the steel is still retained.
If it needs to move anymore once you've begun your engine installation simply use a breaker bar to push into place - as long as it's not more than 1/4in out.
Drivers side engine mount:
Passenger side engine mount:
You can also see from this image how the washers raise the mount up to be square on the existing 720 pad: