1928 3-CT-2 or 3-CT-4

Info from Aeroflies

3-CT-2 Air Yacht had one Wright J-5 and two 108hp Ryan-Siemens, (imported Siemens-Halske Sh 12). One produced NC4184 c/n 2

3-CT-4 Air Yacht had one P&W Wasp and two 108hp Ryan-Siemens, (imported Siemens-Halske Sh 12). Two produced NC7657 c/n 3 and NC7658 c/n 4

The N-number in this photo is not clean, looks like 418?

The engine on the wings are definitely Ryan-Siemens, but the engine on the nose looks more like a P&W Wasp than a Wright J-5. Could this 3-CT-2 have been converted to a 3-CT-4?

There is a number on the front which looks like, No 12. Could this be an aircraft number in the airline's fleet?

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