Property transfer forms on death of tenant in commom

This may be a question already asked. My father recently died and was tenant in common with my mother of their property.  Under the terms of his will his share of the property is to be split evenly between myself and my brother with my mother's 50% ownership unchanged. I have just got grant of probate on my father's part ownership ( they really had/have no other assets) and was wondering what form or forms I need to complete to re register my fathers 50% ownership, leaving my brother and I with 25% each and my mother with 50%. I'm sure my father did this 10 years ago with the best intentions but it seems a bit of a headache.

Peter - it is a Q asked a lot and the answer is provided in our online guidance 
The trust/% shares arrangement is quite common and isn't a headache from a registration perspective as we register the whole of the legal ownership and that always has to be transferred as such.
So in cases of joint owners, irrespective of whether they are TIC or a trust etc is involved, when one of them dies the legal ownership passes to the surviving joint owner. Probate is not needed as a result to deal with the property and the surviving joint owner can, if that's what is wanted, transfer the whole of the title to themselves plus a beneficiary for example as here

Thanks Adam
So in this case, I forward my grant of probate with TR1 and that should suffice as I am executor .....or AP1 ?

Peter - you would need form AP1, TR1 and a certified copy of the probate. Plus forms ID1 or ID3 for each person re identity verification