[oil pan 4]

The only conversion that I know to be 100% off the shelf is chevy S-10 and ford ranger.
Most if not all of these conversions are done on 2wd.
I do not know of any 4x4 conversions.

For some one to do the one motor per wheel, just forget about it.
Honda and Toyota spent a lot of time trying to solve it, then GM couldn't figure it out, they had to buy the technology from Toyota and this was for front wheel drive only.

Save your self a ton of time and don't depend on other peoples charity.

If I understand correctly what you want the fastest cheapest way to make it happen by far is to get a 4x4, tear out the transfer case transmission, run it 2wd and stick a motor on the front diff some how. You would have to run the most insane front diff ratio you can find, 6.xx would work with a lot of motors.

Oh and you can forget about having a old 3/4 ton suburban with 3.0x gears.
A 3/4 ton suburban will likely have a 10.5 inch full float rear end. If you are considering towing anything near 10k you should be using a full float rear.
The most common ratios for this rear is going to be 3.73 and 4.1 ratios. The numerically lowest you will find will be 3.42. The Numerically lowest ever made was 3.21.
A typical gear set for a 10.5 full float is around $400. The no so typical 3.21 ratio can only be found at one place and they are $600.
I just went through this to get a 3.21 gear set for the 10.5'' full float on my 3/4 ton suburban. It has 4.1 gears and that's not going to fly.
I am not even going to bother with 4x4. I could have used it maybe twice from 2006 to 2014 on my half ton suburban. To get more traction I am adding an ARB air locker and building tire chains.

You could try to tow 10k with an 8.5'' semi float 10 bolt rear but that would be a bad idea.
The highest tow rating I could find on a vehicle that I know only came with the 8.5'' 10 bolt is 5000 too 7000lb.

There are only 1 or 2 people on the diesel forum that have put a cummins in that generation of suburban. They only had to modify and fabricate everything.