Hang on... You have set up a new tank and now are asking whether the fish will be okay together.. now they are already added? You really should have researched first. Why the "Help?" - are you seeing any signs of trouble that we can help you with?
Seems a little backward to me - But you have been Great in asking so I dont mean to be mean.
The neons, as they are in a new tank may be in trouble. So dont be too upset if they die. You may be better off taking them back to the shop. If you can - get a few more cories to go with the other 2. A group of 4 would be good in that tank. (Cories and kribs like the bottom area of the tank - so you dont want to crowd it up too much) You could then add neons again (group of 6 or so) after the tank has been running for 4 or so months.
Yeah - wait to see how well those fish do, and then after a couple of weeks I see no problem with adding a few more more guppies. Remember these WILL breed though if you have males and females (each male should have 2 females) so you dont really need to buy any more - just raise the babies.
Good luck with the tank.