Does the OP bolt length change and is the Mummert Movie on oil pan gasket bolt/lock washer technique applicable?

According to Tennessee's oil-pan-gasket installation instructions, no sealant is used. As far as fasteners go, I'm using 5/16-18 x 5/8 serrated flange bolts. Serrated flange bolts are commonly used to attach oil pans. ARP sells them, but I bought mine from Amazon. Not having another gasket to compare thickness, I hope that 5/8 is long enough. The gasket instructions don't say that longer bolts are required. 

I installed the Tennessee Gaskets oil pan gasket using the factory 5/8” long bolts.  No sealer was used as per the instructions.  It’s been over two years now and zero leaks.

Here’s the link to the instructions.  Also included the link to the post on this site regarding that installation.
http://forums.y-blocksforever.com/FindPost168090.aspx
"Real Gaskets Tennessee" (RGT) oil pan gasket

Lorena, Texas (South of Waco)

👌

I ordered their oil pan gasket back in late ‘24, and just now got around to opening the package. Turns out, they sent me a trans. pan gasket by mistake! Packaging/instructions appear universal (NOT product specific), so just didn’t notice it’s smaller size. They are closed until after the holiday, but I’m curious to see if they will stiff me, since the return window has long elapsed. Stay tuned.

6 VOLTS/POS. GRD. NW INDIANA

I'm inclined to believe that they'll make it right. What vendors of classic/antique auto parts need to realize is that these vehicles aren't daily drivers; therefore, parts aren't necessarily used right away. I have new parts that were purchased several years ago and are still in boxes.

They ARE sending me a free replacement, and don’t require I return the trans. gasket.
BTW:  Turns out, the package labels appear the same, but the text IS different. (I saw the words ‘oil pan gasket’ & ‘silicon’, and just didn’t notice the word ‘JAGUAR’). If anyone owns a ‘69-78 XJ16/12, they are welcome to it (?).

6 VOLTS/POS. GRD. NW INDIANA

So, I installed the oil pan (etc.) with the silicon gasket. Followed all the instructions to a ‘T’, BUT, ran into a quandary re. torquing the stud nuts. The builder had sealed the studs into the retainer with RTV. and there was enough left on the threads to load the torque specs. Couldn’t find any specific data that indicated whether the nuts get the same torque as the bolts either, so I just made sure the lock washers were flat, and then gave a little extra twist. The gasket ended up straight all the way around, except it creeped out about 1/32” at the rear. The gasket tech person suggests I should just loosen and re-torque everything.
At least, now I know how to use a claw-foot torque wrench attachment (pick-up tube to pump nut) 😁. Mummert’s installation video didn’t specify any thread sealer there, but I suspect some Permatex #3 wouldn’t hurt (?).

6 VOLTS/POS. GRD. NW INDIANA

Ted Eaton recommended using a sealant on the stud threads that go into the retainer; otherwise, it would leak. Although it hasn't been that long, I think I might have used Loctite Blue. 

The OEM-type studs have interference-fit threads on the ends that screw into the retainer;I bought mine from Hill's Thunderbird. Initially, I thought that they didn't fit; they do, they just require a little more force but won't strip the aluminum retainer. Even though the interference-fit threads are supposed to provide a better seal, I still used sealant. 

By the way, Tim Hill is very helpful; needless to say, so is Ted Eaton.