nah if you have it out easier to fully tighten than fiddling about in the case, but there again whichever you find easiest will do.
we better be seeing pictures when this is all done, or else......................
hope its going okay matey.
just remember to take ya time with the cables, have a look at it and work out an idea of how to get everything where u want it, cable ties etc are useful to keep things tidy and out the way.
Go back to this standoff issues, they shold NOT be at separate heights, screwing a mobo into separate heights will flex it, and might cause damage or failure over time.