He had his flesh magically removed by D'Spayre in Juggernaut One Shot while his powers were weakened, yet he still stood there talking sh*t while D'Spayre was in disbelieve (and that wasn't 8th Day Juggernaut). I personally think that it doesn't need to be 8th Day Juggernaut to make this fight good, he's still dangerous regardless. Surfer may win, but he'll be limpig home after this fight.
(And also, during 8th Day, Juggernaut's strength was only augmented when he was being called with the rest of the Avatars, for those that didn't know.)