When I was shopping, I had no block due to the R word.
Cracks in the heads, cracked block, turned crank, oversized pistons which is a definite no no in a 7.3. nothing to rebuild, no parts to use in the rebuild.

I was not going to ship a piece of junk that was worthless except for scrap metal.

 

It looks like Franklin does the rebuilds for my local International branch. Diesel Auto services sleeves all of their motors and swears by doing so. The person I spoke to said he hadn't seen one come back cracked in the 2.5 years he'd been working there. In fact he said no warranty claims in that same period. The DAS rebuilds are expensive, the long block is reasonable $3800 U.S. but freight adds a bunch. $1000 cdn core charge for the long block. Mine still runs so I think it's a good core. Once you head towards drop ins the price gets up their pretty quickly. 5800 U.S. plus freight 2 ways and the core is almost 3000 cdn. The search continues. I talked to a very nice person in Missouri yesterday who knew just about everything about trying to put a ZF 6 into a non modern 7.3. I think he's pretty much decided it's not doable. I wanted taller gears anyhow and the ZF 6 gets you lower gears and more importantly to him a lower reverse. DPS hasn't called me back. If this was an f 350 I think I'd just go buy another one.

 

My final update for awhile. I opted for the International engine, their factory remanufactured engine. Rebuilt to OEM specs, well duh they were the OEM. It is a Franklin engine, Franklin does a lot of the GM factory engines. No doubt time will tell. I'm looking forward to oil pressure greater than 10 at hot idle. I always thought the end of this engine would be an ominous knocking sound from the lower end instead it was just a slow loss of power as it overheated into oblivion. Does anyone ever use pyrometers on non turbos? Given the slow and steady invisible loss of coolant over days I never caught the problem and temperature gauges don't read air so I got no warning. I imagine I'll be vigilant for awhile but it would be nice to have another source of engine temp feedback. Maybe oil temperature?

I was sorely tempted by the Diesel Auto Services rebuild service. What stopped me was the exchange rate which isn't very favourable at the moment and the 14 working day wait to even start putting an engine together. Add shipping and the trouble with brokering the shipping both ways and it was all too complicated for me with my limited time budget. I'm about going nuts without a truck. Going from a Super Duty long chassis to nothing is a big swing. I was used to not having to decide which of my 3 jackhammers to keep on the truck. Thanks Dave for your intial advice, it shoved me in what I hope was the correct direction.

 

My fingers are crossed for you.
I would try to get a copy of the build sheet from Franklin, that way you have an idea of exactly what was done.

I tried to get one from Reviva with the second engine, they told me that was confidential information.

I guess they did not want me to see that 5 unsleeved cylinders were bored .020 over and the three sleeved cylinders were also bored .020 over and a set of .020 over pistons were installed in a 7.3.
The cylinder walls are thin enough at stock bore.

 

All I can tell you is it is black. They wouldn't release it until I physically inspected it for damage. I guess I could annoy the folks at International one last time, hey guys, do you have a build sheet for that engine? Very steep core charge, 3,300. The only requirement is no holes in the block and will it spin 360 degrees. Mine was still starting so I guess I qualify. The transmission is now proving to be the sticking point. Nothing local and the only used one comes with a 3 month guarantee. Ford made noises about something remanufactured with a one year warranty. Out of Oklahoma, Light Truck maybe? I think I better start a new topic here. I've got a lot of ZF questions.

 

Just an update, the engines in along with a new LUK clutch, single mass flywheels and remanufactured ZF 5 transmission. I just got it back late today. It is so very quiet. The single mass flywheel is something I should have done years ago. I have no idea how well the engine will fair. time will tell. For now it's a lot less noisy than the old one and it has a lot more power and overall it's just a lot smoother. I have 2 yrs to break it and then it's my problem if it goes. Oh, I got the kingpins done too.

1988 F Superduty, long chassis dually 7.3 IDI ZF 5 transmission with an 11 foot utility bed