Receiving gifted stock from Father from Grandmother passing away

I will be receiving a multi 6 figure gifted walmart stock within next month or so. My father is splitting up my grandmother's inheritance between himself and my brother and I equally. She passed in the beginning of August. Im aware of the step up cost basis my father will receive on the shares and believe I also receive same once he transfers them to me. My question is based on some research is if I sell soon, I will pay short-term gains on it versus holding 1 year after grandmother's death.

I personally don't like single stocks and was planning to put 80 percent into sp500 and hold 20 percent SGOV or HYSA for future dream home.

Would you guys take the hit on any appreciation of stock price from day she passed and when I officially sell while paying short term versus risking holding a single stock for a year?