What a transformation. You would scarcely recognise it as the same gun.
John Knibbs says of the gun
Batch of guns starting 58530 and then ending 59029 - Date of manufacture - june to nov 1912, period of dispatch - june 1912-january 1913
and then he goes on to say
Mostly Standard pattern .177, and .22 , with one light pattern. 92 numbers not issued
so it looks like you may have that solitary light pattern.
Great work !!
Lakey