Big Dan: Dates to 1975, listed as a native from Monroe county, Holly Grove, Arkansas from D. Welchel. It is a large oval nut with good production but, as with many large nuts, can have problems with nut quality. 151, 477, 486 Hortsci 13:522-532; Pecan South 7(1):38-41; Pecan Quarterly 18(1):20-28; USDA, ARS, Pecan field station log book.
Hilton: G. E. Kenknight research notes and comments, this one seems to be a grower selection from central Mississippi. 57 nuts per pound with 53% kernel, scabs some, early nut maturity, good nut quality. I have not found any further details.
Edit: added the nuts per pound and percent kernel for Hilton