7050 Engine Swap Questions

First off I wanted to thank you ahead of time for any help that you can provide and ask that you please bear with me because I am new to tractors.  I have extensive knowledge working on cars and gas engines, however have never touched a diesel or a tractor. I recently bought an AC 7050 from a friend to put a snowblower on for my yard.  The tractor spent the last ten years as a pump tractor for their manure hauling business.  They sold it because of a small knock that it had developed.  They assumed that the tractor would last for a few years with the knock if all it was used for was blowing snow.  Unfortunately the tractor had a different idea and decided to throw a rod through the side of the block while running barely off of idle and only making it 150 feet down my driveway.  They have been more than generous with making the situation right which means I was now shopping for a new engine.  Thanks to the help of another member I found on this site I have located a replacement 426 motor from a 1981 N5 combine with 3200 hours.  The motor is complete including the turbo, injector pump, etc.  It has been stored in a shed for the last two years.  My questions are as follows:

1. How close to a direct drop in is this?
2. If I understand correctly from Googling, the injector pump and injectors may be different.  On a diesel, does this matter if they are included with the replacement engine?  Can I simply attach the fuel supply line and call it good?
3. I believe the oil pan is different.  Can this be swapped from the old motor?  (Are there any block or casting changes?)
4. Along that idea of block or casting changes, will the rear of this block mate directly to the existing tractor?
5. I assume that this engine uses some form of a flywheel.  Should the original flywheel from the tractor be used or should the flywheel from the new motor be used?  (In other words, are both crank and flywheel assembly's balanced the same and do they mount the same?)
6. I believe this new motor is rated at 190hp in the combine.  Will this be a problem for the tractor?
7. In regards to the replacement motor, after a diesel has sat for two years, is there anything that should be checked before operation?
8. Are there any other considerations that I am not thinking of?

Again I appreciate any help and knowledge that you can provide.

Quick look at parts shows N uses Ambac pump so a little adapting to fuel lines is in order.

Thank you for the assistance.  I will begin by browsing through the parts breakouts from the link that was supplied to try to answer most of my questions.  That should get me a good start.  I will post any other questions that I have.  niel ev, I may take you up on that offer once I have a better understanding of the parts break outs.  Again, thank you for the help!

Forgot about that front plate.Even though the pump is different,I think that plate is the same.Looks the same on my 220 VS 8070 where the pump goes.With the engine laying on its side(a little downhill to keep the lifters out of the way) you can loosen rocker shaft and get push rods out of the way to pull the cam to switch plate.Check for excess brg play in pump drive idler(doubt there's a problem)while in there.Recommend conversation with Niel.

Not all N5's had AMBAC model 100 pumps. If yours has a roosa master, (most did)you could swap the tractor pump over to the combine engine, that way the electric shut-off/manual shut-off issue is taken care of, as well as the power output. I really dont think you even need to change the pan, even though they are different, I dont think it will interfere with anything since the axle is forward, plus you get more oil capacity. The rear plate and flywheel from the tractor will need to be put on, along with the rear seal/sleeve, and rear sealing ring and the cam hole seal. good luck, Ed.

I would put new rod bearings and bolts in it before you put it in the tractor so you don't end up with the same problem. Would have been nice if Allis would have increased the rod journal diameter on the 426 back in 1973 when the 7000 series came out.

I am far from an expert but we did kind of the same thing when we put the generator engine in our 220. When I noticed the front mount problem I thought about doing it Docs way and re doing the plate. Ended up swapping the pan, front cover and plate and it wasn't realy that big of a deal. You will need an engine manual and a puller set up for the cam gear at least on ours we did. Prolly need the seals for the injection pump drive shaft as well.  Spent 2/3 of a day in the shop most of it spent cleaning parts.  We had to swap a lot of other things like filters,'stat housings etc etc. ALso gave me a chance to pull a few caps and look the bearings over. I had a complete gasket set on hand and was glad I did. probably cheaper than all the individuals and certainly lots quicker and nicer to have them at hand.

Well I am still working through the planning stage of the project.  I have been talking with a couple of local tractor mechanics getting up to speed on working on one.  Neil, I still plan on giving you a call as well.  In the meantime though, I thought I would add a couple of pictures of the window I put in the block.