I brought in with me a megatherium, a rock drake and a wyvern. They were lvl 675, 678 and 575 respectively and yes, i did set my wild dino limit to lvl 450. Its that easy.

NOTE:

If you do bring a wyvern, note that it can damage your other tames with its SPECIAL ability, i.e-i brought a fire wyvern which was damaging my rock drake through its fire attack