I've got a great engine-rebuild book here that I'm using to rebuild my L98, but when it comes to the oil pan, it's instructions are for someone using a multi-piece oil pan gasket (the cork kind). It's telling me not to torque more than 8-10 ft/lbs on the four outer bolts, but, again, it's talking about someone using cork gaskets. I believe that this is a Felpro gasket I'm using, and it's a one-piece part made of pretty thick rubber. Shouldn't I tighten that harder than I would with the standard cork one? (I tightened it to the torque specs in the book, but it seems like I could tighten more...)

 

i just rebuilt my engine and the kit came with the four piece oilpan gasket set..then i noticed leaks so i said screw it and went and bought the fel-pro one piece gasket and yes you can put a little extra torque on the outer bolt with no problems....just a little though.lolz these one piece gaskets are sure handy when it comes to changing the oilpan gasket with the engine in the car...

 

Torque to factory specification
When you install the rubber gasket, make sure the oil pan flanges are flat, and that the pan and block are CLEAN AND DRY.
Put a small dab of RTV ultra blue in each corner, (where the timing cover meets the block and where the rear main cap meets the block).
If the motor is still in the car, get some fel pro gasket cement, and put small dabs on the block to hold the gasket in place.
If you try to use High Tack or silicone sealers of any sort, the rubber will be lubricated and squish out, rip, and probably leak like a sieve.
If the motor is on an engine stand, you got it dicked, flip it on it's top and let gravity hold it in place while you install the pan.
Again, torque to FACTORY specs. They built it, they know how to put it together.

 

Just re-read your post, since you have torqued it to factory spec, leave it alone and see if it leaks, you can always tighten it more later.
I would suggest re-torqueing it after a couple hundred miles.