Saxe-Coburg-Saalfeld presents a complicated situation where North and South German currencies overlapped. The first thing which is clear is that the Conventionsthaler was adopted in 1763 and subdivided into both 120 Kreuzer (South German) and 1⅓ Reichsthaler (North German). Can I suggest the following changes? First, change the present currency to
Thaler (1680-1763)
1 Thaler = 24 Groschen = 288 Pfennig = 576 Heller • 1 Ducat = 2 Thaler
I think this may gloss over other complications but it seems broadly consistent with the coins. We then need to add a new currency
Conventionsthaler (1763-1826)
1 Conventionsthaler = 120 Kreuzer = 144 Kreuzer Land Münze = 1⅓ Reichsthaler • 1 Reichsthaler = 24 Groschen = 288 Pfennig = 576 Heller • 1 Ducat = 2 Conventionsthaler
Is that clear enough or would it be better to separate the two systems entirely?