That should work.  You may want to update the power supply or using adapter to provide power connectors for your RTX 3060 card.  If you have to replace the power supply, that will be a pain as it will require to remove the wirings from underneath the motherboard.
So I'm currently working on the workstation and I was wondering if these would work for the workstation. Also is Asus the best graphics card type ?
Will the following 2060,2070,2080,3050,3060,3070,3080 work in a Dell Precision 
T3500 ?