The changes to 230.46 that ggunn is talking about were new in the 2020 NEC. But most actual Polaris brand connectors are fine now.
Adding solar to a 100a service. Plans call for a LST but there's no access to the conductor outside the home and feeder runs through the wall behind a shower surround. My thought was to add a 8x8 under the meter, add 3 position polaris taps for my 6ga pv conductors. Any code issues here?
The pv disconnect will be within 10ft and is fused. I'll need to bond at the disconnect as well, correct?
This is rather unclear to me. Does LST stand for line side tap or load side tap? Are you trying to follow the plans or saying you need to do something different?
Under the 2017 grounding and bonding for a supply side connection is pretty vague. Under more recent code cycles they are clearer that you should treat it like another service disconnect, i.e. bring the neutral to the PV disocnnect and bond it to the enclosure and EGC. Just make sure you have a white or green wire going from the PV disconnect back to the service neutral.l, and let your AHJ decide. If a load side connection, keep ground and neutral separate like any other circuit.
An 8x8 is code minimum for 1-1/4" conduits entering, I would suggest going bigger.
In conclusion, lots of potential code issues with details you haven't mentioned, but the general plan is probably fine.