Here are a couple of links regarding neoprene rear seal installation on the Ford Y.  Also works for the FE and MEL engines.
http://forums.y-blocksforever.com/FindPost145797.aspx  
Neoprene Rear Seal Installation for the Y (and others) – Eaton Balancing  

And here is the link providing information about the Real Gasket Tennessee oil pan gasket.
http://forums.y-blocksforever.com/FindPost165810.aspx  

Lorena, Texas (South of Waco)

FD, I just ordered the Tennessee silicone oil-pan gasket. Once received, I'll message them & let them know that they should hire you as their spokesman. I figured that there might be a run on them, so better to get my order in today. 

Merry Christmas!

My experience with the silicone gasket has been very good. Perfect? Well, my oil pan is to some degree not flat and true like from the stamping plant even after attempting to work it flat as best I could. But just comparing cork to silicone with everything else being equal, the silicone wins.  As always, Ted did a good deed by installing the first prototype gasket on his dyno muel and gave it a thumbs-up. Do you folks think it would be worth wile to have a valley cover gasket produced from the same silicone material or, valve cover gaskets?  That is, only IF Mummert doesn't offer those particular gaskets in neoprene anymore?? Real Gasket Tennessee does offer silicone gaskets for the FE and SBF engines as well. My first encounter with their silicone products was valve cover gaskets for aircraft engines - they were excellent. They were great folks to work with developing the oil pan gasket for our Y-blocks. I think they may be open to suggestions/ideas if there are some sales potential. 

64F100 57FAIRLANE500

I’ve used 4 of the Best Gaskets seals. The neoprene was fine, the orange silicone failed immediately. It was replaced with the black neoprene and was fine. Used a sneaky pete, just backed a couple mains off a bit. Went right in. Follow Ted’s instructions on his site.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

FD, my engine pretty much leaked oil from everywhere. If I can ever get it rebuilt (I have most of the parts), I want to make every effort to eliminate those leaks (if possible). I have the silicone oil pan gasket on my eBay watch list. 

Real Gasket Tennessee makes a lot of gaskets, including gaskets for Ural & Moto Guzzi motorcycles (go figure), but they only make the oil-pan gasket for Y-blocks (go figure). 

55blacktie thanks for mentioning the silicone oil pan gasket from Real Gasket Tennessee.  I totally forgot to comment on it.  The silicone gasket, IMO has proven to be superior to the cork gasket after running with that gasket all summer. It also can be reused multiple times. It should also eliminate the need to piece-meal in a section of pan gasket if in the future the timing chain cover was to be removed. So if you do indeed drop the pan, I highly reccomend the silicone gasket and follow the supplied instructions. 

64F100 57FAIRLANE500

Read Ted Eaton's article. He used the neoprene seal, not the rope-type.

I've read fixing the rear seal is very difficult (I've done a couple of other cars), but from what I've heard the rear main seals don't always stay seal.  I read the old rope/asbestos seals worked best and the tolerances (crank-block) didn't have to be that tight with the rope.  If there was something proven I would consider it.   I wont be driving the car for the winter months here in NJ............ but I have a few more projects already planned.

Ross, speaking from experience, I think you've stumbled onto a never-ending journey; the more you dig, the more you'll find that needs attention. It's particularly true when the vehicle has been neglected for many years. Now I'm waiting for you to ask about replacing the rear-main seal without pulling the engine. If you're going to remove the oil pan, you might want to consider buying this:Ford -Y Block Oil Pan Gasket -RG-10701-C1 Silicone from Real Gaskets Tennessee, $45 on eBay. Maybe you've seen it mentioned on this forum.

I wish you the best. 

I didn't fit the gasket to see where I would have to cut the old gasket, I assume it's where the timing cover meets the block.   From what you are saying I can leave the oil pan in place (minus the 6 bolts that hold the timing cover) cut the old gasket and use a sealer for the "seams".   
I also purchased a full size pan gasket which I am leaning towards installing, since I will have a couple of weeks waiting for my Damper to be rebuilt.   If others here have used the short gasket with success I wouldn't mind using the short one