Numpad with letters visible

[DarrenNewsgroup]

I have a 6 digit number I need to enter into an app but I remembered it as a 6 character word. I have a different keyboard that shows the numpad with numbers and letters 2abc, 3def, 4ghi etc. (just like the old T9 input on Nokia 3310s etc). If I click on 3def the keyboard enters 3 which is exactly what I want. The app now refuses to run with that keyboard but will run with HeliBoard. I tried doing a custom layout but could not get this effect. Does anyone know if this is possible. Thanks.