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I removed the rear main cap, and found what was left of the rope seal!! It really fell apart. Totally shredded. I spent a good part of the day cleaning the oil pan mating surfaces, and other main mating surfaces. The upper part of the rope seal was gone, so that was easy to remove!
I'll get help from my father in law in a few days and install the upper rope seal. I figure with one Person revolving the crankshaft an me pulling the seal in will work better. Getting a nice cut on the top rope seal after it's in is going to be tricky. I will have to rig up some Sharp razor blade on a 90 deg angle or something. Using a modern/viton seal here would be easier if it meant no cutting after it is installed. I soaked the McCord rope in some fresh oil before inserting it in the Main cap, it is pretty supple going in. It sure will be an improvement over that shredded nothing that was there! Geez.

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Almost looks like it was dry when the engine was started. Maybe some assembly lube on the crank surface when you put it back together would help.

I am not a big fan of trying to pull a seal into the upper groove. It has not worked well for me.

I think I would go ahead and cut the bottom half of the seal, lay it in the groove, lube it, torque the bearing cap in place and even spin the crank a bit. Maybe even let it sit assembled overnight. Then I would carefully take it out, drop the crankshaft as far as I could by loosening mains 4,3 and 2, and try to slip that nicely formed seal up into the upper half. Then you can remake a new lower half and put everything back into place.

I still have the transmission in the car, can I still slowly back down the other main caps to lower the crankshaft a smidge? I don't want to bend the crank. I already formed and cut one rope into the rear main cap. Guess I can bolt that in to form it nice to place in the top. I have a second rope seal if I screw one up, but I hope to get it right. I will lube it with oil or Paste for sure!

It is quite OK with the trans in the car.. You are not going that far.

I snuck 1/2 Hour into the garage, trimmed the ends of the rope seal to a clean 1/16 inch. Installed the main cap -lubed with oil- and torqued to 92 Ft-lbs. Spun the crank 2-3 times. I'll open it up in a few days and see what the rope looks like.

No dice with the origianl style graphite rear main seal. I was able to get the seal about 1/2 inch into the top half of the seal, but then the rope seal broke. I couldn't get the crank to drop. I believe the trans is holding it up.
Rotating the crank while pulling with the "chinese handcuffs" thing didn't help much either.
I'm thinking the next thing I will try is to get my hands on a more modern rubber 2 piece seal. My hope is that I could somehow get that in better.
A while back it was mentioned that a chrysler slant six 2 piece seal with a spacer will work. I'm going to see if I can get my hands on something that will fit. (FelPro BS40240 is the number I find online)
Here is the thread where it was mentioned:
https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=15943&viewmode=flat&order=ASC&type=&mode=0&start=0

I'd measure the diameter of the sealing surface on the crankshaft, but my micrometer is not deep enough to get around the crank. If anybody knows this dimension, please tell me. I figure with that dimension, and by bringing the rear main cap to my auto parts shop, I might be able to get a 2 piece seal here in metric land.

Argh!

What would be really cool is if I could get a rubber O ring that I could cut in half, stretch it so it is thinner, then install it, and when it returns to it's original length, it fattens back up.....voila! Now I'm dreaming.....

I found this cool thing on google. It is an old patent from 1952 for a rope seal installer. I think I could make one by cutting and then doing some grinding on a junk main cap.....It pretty much just works like a little funnel for the rope going in.
The one rope I broke already becasue the outside of the rope started to hang on the block. This might help with that.

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I measured the diameter of the sealing surface of the crank where the rope seal sits. 73.75mm or 2.903 inches. That makes it an unusual size, and finding a replacement from another mark not so easy. I have a graphtight seal in the mail, and I'll see if that goes in any easier than the NOS ones.
I plan on making an aluminum "funnel" which I hope will hope allow the rope to be pulled in easier. Here is a pic of what I'm thinking of.

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Oh Happy Day! I made my "funnel tool" out of a piece of plastic. I was able to use my spare block and crank for trial fitting and with some sawing, sanding and files I made this handy tool! It actually worked and I was able to install the upper half of the rear main seal!!!
I also got a graphtight rope seal, and in the kit they sell, one length is about 4 inches longer than the other length of rope. This allows you to place the "chineese handcuffs" tool about 2.5 to 3 inches around the rope seal so it gets a good hold on the seal as you pull it through the block.
I also had my father in law helping to turn the crankshaft as I pulled the seal in. The instructions say to just use motor oil on the seal, so that is what I used.
Tomorrow I just have to cut the ends, install a pin in the lower rear main cap to keep the lower rope in place (1/16 inch diameter pin) and install the lower rope and cut the ends....Then oil pan etc....Keep you fingers crossed that this seal holds.
I think installing the pin in the lower half of the rope seal to keep the thing from spinning may be important. That was not installed the first time.
OK, here are some pics of the rope in place. You can see the tool held in place by the bolts, and also a few pics of the tool itself!

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