I figured out what I have and I'm trying to find part numbers for a clutch kit. I don't want to r&r this ***** twice, so I think I'm going to just do a solid flywheel instead of stock dual mass setup. It's an 88 International, 7.3 N/A IDI and a Spicer 5 speed ES42-5A. Have seen kits for everything except for an N/A 7.3 IDI. Just need a stock replacement clutch, was recommended Luk brand, anyone know part numbers? Thanks

 

https://www.pgttruckparts.com/Spicer...ion-s/2593.htm
Page 7 shows some input shaft options.

The LuK RepSet catalog shows P/N 07-225 for a stock 7.3 SMF, but the spline on the clutch is 1 1/4" x 10 splines.

Unless they used a non-standard input shaft that matched the Ford one(no clue if that was a thing), you will probably have to find another clutch disk that matches whatever spline your transmission has. Or, not sure if a local shop can just turn the input shaft down from, say, 1-3/8 to 1-1/4 and deepen the splines to match... Not sure the best option here, and I'm not sure you can tell either until you pull it apart.

Even pictures would help - You might want to get under the truck and pull the inspection cover, take pictures of what's there and see. It might be a SMF, I don't know - you can tell by having the trans in neutral and physically rotating the pressure plate back and forth. If it doesn't move, it's probably a SMF. A DMF should have around 3/4" of "free play" back and forth.

edit:
I'll bet you have a 1-1/2" input shaft, judging by the "navistar" applications near the end of that document.

 

Have you talked to an IH dealer? Im sure they would be able to give you a part number, and probably sell it to you.

 

this^^^
if i remember correctly the big truck transmissions use a different clutch setup than the pickup uses. international truck parts department is going to be your best place to ask.

 

And have the last 8 digits of your VIN number handy, that's how they do identification down at International. They can't/won't give you the time of day with year, model, options, etc.