The GRX 600 series cranks are not compatible with our powermeters. They have a hollow channel on the inside of the crank that doesn't support the installation of our powermeters. We are only able to install PRECISION on the GRX 800 series of cranks.
Our series of Shimano Ride Ready powermeters (GRX 800) are compatible with the GRX 600 as they share the same Hollowtech II bottom bracket system. You will just need to check clearance and purchase the correct length.