Questions about swapping in a 518 on my D200

[Lonesome7.3]

Being since my 727 fell apart recently I am jump starting the swap I have been planning. The problem, this is new territory for me. This is my first Dodge and my first Dodge mod. Someone brought a company to my attention that sells everything I need for this conversion and who sells a rebuild kit to fix the problems the 518 has. Can someone please tell me what kind of problems the 518 has? What should I be aware of before buying one and what should I look for when I do find one? Also, is there a better choice than a 518? This is going in a two wheel drive, 318 powered, ¾ ton truck that gets used. I do take very good care of it and because it belonged to my granddaddy I plan a full frame off restoration in a few years. But this truck does pull trailers, hauls hay, and other various uses you would expect from a truck. Also, what kind of odds and ends should I search for in junk yards? I know there has got to be a bunch of details that will have to be addressed in order for this thing to work and be reliable.

 

[typ4]

The biggest concern is keeping the cooler working so the lube oil does not stop flowing to the od unit. It will burn up quickly if the cooler plugs. When I do them I go up one size on the steel lines and install a BIG aftermarket cooler, the ones in the late radiators, are junk.

 

[Lonesome7.3]

I have one from a Cummins pwered rig with a 727 that huge with massive cooling lines.