Hanoverian SYW Artillery

With the below, I present my new scratch built Hanoverian 30-pdr or 8 inch howitzer. For long I have been in search of good source that would provide a good general picture on how Hanoverian ordnance would have looked like in distiction to my in depth researched and presented French or Prussian ordnance.
I still need to make a visit to the State Archives of Lower Saxony found in Hannover and Buckeburg (much of the former Brunswick-Luneburg territories). The latter does keep a lot of artillery drafts—not so much Hanoverian, I'm arfaid)—while the former has but few drafts listed with the libraries finder.
Its not all that much I have for the time being, but enough to give it a start. Now, lets close in on the issue.
A general overview on SYW Hanoverian ordnance can be found at Kronoskaf SYW Online Source Project http://www.kronoskaf.com/syw/index.php?title=Hanoverian_Artillery_Equipment . Most of this articles content was edited by myself, so there is no need to repeat it all here. This article's focus is the ‘looks’ of Hanoverian guns of this period. Lets first have a look at the result.

The barrels looks are my take based on an illustration found in Scharnorst, Handbuch für die Officiere, …etc. Erster Theil von der Artillerie, …etc., publ. Hannover 1787. It shows a Hanoverian howitzer barrel of the 1780's fielded new ordnance. Its most distinctive feature is the odd rounded breech at the base of the barrel instead of a button. I believe models cast earlier has a much similar construction. The carriage bracket cheeks are based on a Danish construction. Its most distinctive feature is its cornice shaped part in front of the trunnions. A feature, often found with mortar stools.

Above see some W-I-P images of the piece placed next to the French 8 inch howitzer. 
The manner of the iron straps I have done based on a draft of a Hanoverian 24-pounder carriage. The songle draft I could find so far.

Source: copyright restricted
Digital Collection Württembergische Landesbibliothek.
It is published here for purely academic use without any commercial intention.

I identify the above draft as Hanoverian, for it includes the ‘Calenberg Fuß’ as foot scale. It was the official unit used in Brunswick-Lunebourg, and I'm not aware it was used in any other German principality. This was the easy part. More difficult it is to make an assessment regarding it's dating. My best guess would be to date it at around 1720, but it could also be late 17th century as well as it could be after 1730 to mid 18th century. Very difficult to say.