Sir Harry, it seems, was full of praise (6)
I believe the answer is:
lauder
'sir harry' is the definition.
(I've seen this in another clue)
'it seems was full of praise' is the wordplay.
I cannot quite understand how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is located in the answer.
'praise' could be 'laud' (lauding is a kind of praising) and 'laud' is found in the answer.
A single letter 'r' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for lauder that I've seen before include "Knighted Scottish music hall comedian" , "music-hall entertainer" , "One celebrating" .)