Unfortunately, Stealth doesn't sell the wiring harness separately from the ball mount portion for the # SH67FR hitch. What you can do is purchase the hitch along with the ball mount and the wiring which provides a cost savings. The hitch, ball mount and wiring is sold in a package as part # SH67FRT.
If you'll be towing with that hitch, you will need the ball mount assembly included with the # SH36FR wiring package, as the ball mount is a proprietary assembly that nobody else offers. view full answer...
You always want to go by the lowest-rated component in any towing set up, which in this case is the 200 lb tongue weight of your 2019 Volvo V90.
So that is the necessary tongue weight you will need to abide by after installing the Stealth Hitches Hidden Trailer Hitch Receiver with Towing Kit # SH67FRT. view full answer...