How can I combine shipping for a two-box product?

[VanCuren2021]

I have a product that is too big to ship in 1 box. If I make 1 product, the weight is 170lbs and it won't ship UPS and give a shipping cost at checkout.

They way I've gone around this is to have Product Box 1 at 85 lbs and Product Box 2 at 85 lbs. This leads to confusion amongst the customer base. It's clunky and I understand the frustration. 

Is there a way to make this 1 product so somebody can add just 1 product to their cart and get the accurate shipping cost? TIA