There's a book of interviews with the Memphis Mafia (Elvis's closest friends), and none of them could recall Elvis making homophobic remarks. Elvis had sideburns, long hair, and wore makeup long before any had become widely acceptable on men--he knew what it was like to be considered a freak and never tried to make others feel that way.
That said, there is no evidence that he was anything but straight. It's very hard to stay closeted in the grave, and if he'd had any homosexual relationships you'd have heard about them by now.
The source for him supposedly being ashamed of being uncut is Albert Goldman's discredited biography, which is full of errors and unreliable. Elvis grew up in the deep south, and would have hardly been the only uncut person there.
If anyone wants to see Elvis at his sexiest and best, watch his '68 Comeback Special--it's one of the greatest performances in rock'n'roll. Elvis wore a black leather suit for the show, and apparently sang so hard he climaxed in it onstage.