What kind of studs you use isn't an issue. You can use the type that have a shoulder in the middle so the only screw in so far or you can get some threaded rod and cut off your own. Those will need to be threaded in all the way until they bottom in the hole. just make them long enough that you have about 3/4-inch of threads sticking up from the pan rail so you can get the nut started on it.
As far as size of studs, I prefer to always use the same size on both ends. If it's 5/16 threads in the block, it's 5/16 threads sticking up for the 1/2" nut.
If you have the time to let it sit and cure, you can do what Lee suggests. But the entire issue is moot if you don't use but a TINY dab in the first place. Remember, the gasket's job is to seal, and they are very well designed and perfectly capable of doing the job. When you put silicone on them, you are doing something the designer/engineer never did, so are modifying how the materials behave. You are only trying to fill any TINY gaps that MIGHT occur between the rubber and the cork gaskets. You are NOT trying to put enough silicone on there to replace the gasket. It's insurance only.
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David
newbie #4153
