If you're buying rods anyway, there's really no reason not to use 6" rods in an engine with as short a stroke as the 327 has. Your pin location won't be high enough to compromise good ring sealing caused by piston rock. The 273, 318 and 340 Mopar small blocks all shared the same stroke, a very short one similar to the 327, I think perhaps just a bit less, w/o looking up the numbers. Anyhow, they used rods of a nearly 6 & 1/8" length from the factory and certainly have never been known for any such problems. I use 6" rods in my 388 Chevy stroker which has a 3.80" stroke. I actually used pistons with a compression height for a 3.75" stroke but that's another conversation. Anyhow, the pin is indeed into the bottom (oil) ring land but using ring supports for the oil ring, I don't consider this a problem. It's preferable to squeezing the rings closer as techinspector made mention of. In using 6" rods in your combination, I can say with surety that your pin location would be considerably lower than mine and would not encroach into the bottom ring land.
I like the 6" rods for my purposes because they help bring the torque on just a little earlier in the RPM band. I considered this especially beneficial in a 3400# car with a 3.07 gear. Not a big gain but every little bit helps if you're building for a specific purpose and goal. You're doing as you should, seeking info, opinions and the experience of others. Once you develop a broad picture in this or any other matter, in the end only you can decide exactly what is right for your goals. Everything you consider must be weighed as part of a total package with an end result in mind. Everything in engine design and modification is a compromise.