What is the preferred connection from solid braid main line to mono or fluorocarbon for spinning tackle? Most of the knots I have researched are shown for conventional reels that do not need to pass over a line roller.

I have only used mono on spinning reels and will be setting up a 8000 size to chunk the surf while targeting perch/corbs with a light 2000/4# setup. Thinking of 50# braid to 30# mono/fluro on the 8000.

You could cheat and use a leader short enough so that it doesn't have to pass through the line roller. Alternatively, the RP knot is small about so that it shouldn't be a problem.

We see two directions, make that three. First, use of a longer topshot of mono with or without a shorter 3 foot section of FL tied to the mono. Casting distance covered by mono, braid used for extended capacity. Alternate, shorty leader 3 feet or so, so the connecting knot is outside the rod's guides. Alternate, use of hollow core braid with in-line leader rigging of whatever length a person deems appropriate, 25 feet being most common.