@prospectguy Luckily, the MPPT inputs on the 18kpv have a MAX short circuit input of 31a|19a|19a. Not sure of your panels ISC, but it shouldn't damage the MPPTs so long as it doesn't exceed 19a on the MPPT 2 & 3. It is pretty close to the max though, so I would be cautious about this.
We already have something in the works that will take care of that for you! That is one of the things the Grid Boss will be handling. Keep on the lookout for more information regarding this new equipment, as I can't share much more, but here is a video going over the new product line. In this, James goes over the Grid Boss and explains it's uses. I shared @ 4:24 which is where he talks about the Grid Boss. The beginning of the video goes over the Flex Boss as well, which will work hand in hand with the Grid Boss. That may also solve the PV input issue you are running into as well.