The former Great Britain scrum-half figured prominently in the first five of Wigan's eight successive Wembley triumphs, becoming the first player in history to win the Lance Todd Trophy, which goes to the man of the match, twice at the famous stadium.
While Wigan were again walking away with the title last season, Salford were winning the First Division and now have the chance to pit their skills against the best in the world in the fifth-round tie at The Willows.
"Wigan are world champions and now we can show ourselves against the best. This will be a guide to see how far we have come. I think we are a Super League team. We won a division this season and did not go up, which is something I have never agreed with," Gregory said.
"I just hope we go out and do ourselves justice as I think we would maintain our status in the Super League, although unfortunately we now have to do it all again. But we've had a good season and do not want it to end at 4.30 on Sunday. You want good things to keep going."
On Wigan's great run, he added: "It will never be beaten, but hopefully come Sunday it will be over. It's a tremendous effort by any side in any sport, but records are there to be broken."
As well as Gregory in the dug-out, Salford will have several ex-Wigan talents out on the field including the full-back Steve Hampson and the loose forward Sam Panapa, adding extra spice to an already fascinating clash.
n Castleford are poised to re-sign the centre Grant Anderson 19 months after selling him to Halifax for a tribunal-fixed pounds 85,000. The former Great Britain Under-21, who has been plagued by injury, has made only 14 appearances for the Thrum Hall club. Anderson, 26, scored 79 tries in 211 appearances in his spell at Wheldon Road.Reuse content