Assent of Property by executors to beneficiary considerable time after death of owner

My parents had their house registered as  joint tenants. My father died in 1990 but the register was not changed following his death. My mother died in 2001 but again the register did not get changed following her death.
My sister & I were granted probate of my mothers estate & we have a certified copy of the grant of probate.
My sister & I have now agreed to Assent the property to myself & my wife for no monies.
I have completed & had certified ID1 forms for myself, my sister & my wife.
I have completed an AS1 form naming my sister & myself as transferors with myself & my wife as transferees to hold the property as joint tenants, with all signatures in the execution witnessed individually.
I have also completed an  AP1 form with my sister & myself as applicants in section 6 & also as transferors with  my wife & myself as transferees in section 14.
Does my wife have to be named as an applicant as well on the AP1 form?
I will be supplying the certified copies of the two death certificates & the grant of probate as well as the three ID1 forms 
the AS1 form & the AP1 form.
Are there any other documents that the Land registry will require in order to process the application & Assent 
 

Kenneth - panel 6 of the form AP1 should refer to the applicant as in the names of those to appear on the updated register as the new owners. So you and your wife.
We don't need a death certificate for your late Mother as the probate confirms both her sad death and your legal authority as her executors
No other documents to those you refer to, with my small amendment, should be required 

Re the above - out of interest who is regarded as the legal owner in the interim 20 yr + period ?
Can it be true an assent can be put off for many years and enjoyed in the interim by the personal representative ( if the PR is the only beneficiary of an intestate estate for example) then assent the property to a child for example for inheritance tax planning? This seems like a way to make a significant lifetime gift without tax implications because the property is never inherited therefore not part of a potential estate. Perhaps I’ve misunderstood.
I welcome views 

Claire - when a sole owner dies the property/legal ownership forms part of their estate until probate is granted and the executor(s) then transfer the property as appropriate. It is only once the transfer has taken place that the legal ownership changes.
Some properties re main 'inherited' and in the family for many years simply because the executor(s) did not transfer the ownership
We don't deal with the tax implications so would suggest seeking advice from HMRC although there are a number of online forums, Money Saving Expert being one, where such matters are often discussed.