Thank you MonsieurTox and everyone for your interest.
Here is a small project for an Omicron winter weekend, an M-24 Chaffee gun and mantlet.
Helpful modellers posted nice pictures of M24s and other tanks on a web site called
http://www.usarmymodels.com. In addition to the Bronco 1/35 kit and other books i have, these were essential to understand the features of the M24 mantlet.
This is the cast mantlet when viewed from above. When i analyzed it, i broke it up in 3 layers with different angles. The M6 75mm gun is not centrally positioned, its a bit on the left. There is a Browning M1919 coax machine gun on the lower left, and a sighting apparatus hole on the top right.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
- Capture.JPG (90.03 KiB) Viewed 1966 times
View of the M1919 mount and the casting on the sides.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
View of the mantlet of a M24 monument with the hole for the sight plugged. Notice the rough aspect of the casting and weldings.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
The cast marks in the upper plate are reversed... When i flip the picture over, i can make up D76004 and the a star with a G on it. Then a bit higher, i determined it could be a D1314.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
- Capture4.JPG (34.07 KiB) Viewed 1966 times
Basic shapes are created in 4mm plasticard in the 3 layers seen.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
The top section need to be quite round so i will needed to split it later and create 4 layers.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
An hour later with some Dremel time outside, this is the mantlet with the 4 layers. It is slowly taking shape, always comparing to the 1/35 and test fitting it with the turret mount.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
Then two hours later, the mantlet is in it definitive overall shape and ready for detailing. Test fitting with the turret mount show degrees of gun elevation consistent with the one seen on the 1/35 kit, not great but good.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
Calculations were constantly checked against the 1/35 kit. Hand building this is probably not for everyone. Most guys would probably CAD design and 3D print it but it would not be easy either.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
Before continuing on the mantlet, i needed to create the gun. These are the 2 main components; 1 thick wall 8mm brass tube for the gun and 1 10mm brass tube for the sleeve and recoil mechanism. The walls are 1mm thick. Purchased for a few dollars from eBay China.

- RC 1/16 M-24 Chaffee light tank- Dien Bien Phu 1954 - Build
Continuing right away on following post