How to get max Carry-Over stats on a SR?

I've been searching all over for how to get max carry-over stats for my Hell Raider, but I can't seem to find much. I have one Devil Hunter that was evolved using 2 level 1 cards, and have all the materials for another Devil Hunter and 2 Exorcists. How much should I upgrade them to get max carry-over stats? Is it even still possible since my first Devil Hunter was upgraded using two level 1's?

Usually it is suggested to fully enchant the card that is before the final form you want (here for example, you'd want a lv10 Devil Hunter+ and a lv 10 Exorcist+). That should maximize your carry-over stats....

If you had enchanted till lv 10 Devil Hunter and exorcist (no+), you'd probably had 2-5 extra attack on the SR card... so it's not much of a difference and you really don't have to waste gold and cards on that.