Stepped up basis for trust - filing requirements Forms 706, 8971

My deceased fathers property was in a trust and was sold within 6 months of his death to an unrelated party. I did not establish probate, and the value of the estate is below the exclusion.

 

Is 26 U.S. Code § 2032 - Alternate valuation enough for me to establish the property's  basis on the trusts 1041 at the selling price, or do I also need to file form 706 and 8971 to obtain the stepped up basis?

 

Thanks in advance!