Hi LG,
By it's very nature Clomid usually gives you a nice strong LH surge (what the opk's are aiming to detect). It is accurate that 2pm is the optimal time to test. Some women benefit from testing twice daily (I am one!) - this is because of a couple of fators. I have done an opk at 2pm and then another at 8pm and the one at 2pm was neg but the one at 8pm was positive. You can see from that that had I not done the second test I wouldn't have detected my surge and missed my ovulation. (the test at 11am the following day was positive but at 2pm was negative).

So, yes, it can be a good idea to test twice daily or even thrice daily around ovulation. If this is your first month on clomid you may find you don't ovulate when you do usually. I would begin to test earlier than cd14. I personally would start testing on cd11/12. This is because generally you will ovulate between cd13-15 on clomid - however this isn't a hard and fast rule. I am one of those women who ovulate LATER than usual on clomid and you will find that there are a few of me around! Obviously if you are artificially stimulating your ovaries you want to make certain that you know when ovulation is occuring for the best possible chance of conception. This is why it can help some women to test a little more frequently.
Lullaby conceptions has some really affordable and accurate tests.

Each woman will ovulate according to her own body clock and hormone levels. Basically you will ovulate 12-36 hours after that initial LH surge. So for some women it will be quite soon after that positive test and some months it will be a day or so later. Just ensure that you do the deed when you see a positive and for the next coupld of days afterward.

Good luck and I hope you catch that egg this month!