This method of using first and last letters can also be used for Long Codes [type C] and where does the letter come from [ types O and R]
Just watch out for the odd one where the codes/words aren't the same length.
From NFER 11B question 85:
If the code for PIANO is QKDRT what is the code for VIOLIN?
The code has 5 letters and the word has 6.
From NFER 11A Question 67:
(grown [sewn] dose)
(bloat [ ] globe)
Dose and globe aren't the same length, and this one has the added complication that you have to use the last 4 letters of globe, rather than the first 4.
s in sewn comes from the second-last letter of dose
second-last letter of globe is B
e in sewn comes from the last letter of dose
last letter of globe is E
w in sewn comes from the 4th letter of grown
4th letter of bloat is A
n in sewn comes from the last letter of grown
last letter of bloat is T
Word is BEAT. If you work from the beginning of globe, you get OBAT.