Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
You only have to pay tax on the chargeable gain if you are a higher or additional rate taxpayer. If you are then please follow up on this thread.
I do hope that you have found my reply of assistance.
Top slicing relief applies. 32K / 5 = 6.4K which is the slice added to your income in the year of surrender. Does this still push you into the higher rate band? If so you will be liable for another 10% (16/17 rates), otherwise 18%.
As this is income you include it in boxes 11, 19 and 21.
You do not actually have a gain as top slicing relief transfers one fifth of it to income. So you add the 6.4K to Box 10 making it 44993 and adjust the tax paid [box 11] element of 6.5K.
Your tax position for 14/15 is 44857 less personal allowance of 10000 leaves 34857 exposed to tax of which 31865 will be taxed at 20%  and the balance, 2992 at 40%  Deduct tax paid 12318 means that when the chips are down HMRC owes you a substantial sum of money.
Did HMRC explain top slicing relief to you? If they did not then there is a very good chance of your receiving a huge tax bill for the 32K declared instead of the lower amount on your account. HMRC have a very well deserved reputation for not being able to get hold of the stick if they can even find the stick at all and this may well have occurred in this instance.
Well I trust that you will not, but don't hold your breath would be my advice.
Thank you for your support. I do hope that all goes well with you and you get your top slicing relief easily.