Yes as I was saying in the other thread you started, a gen or clone 3135 will likely not be an easy transplant. Your case does not have the milling on the internals that would support the holding of a 3135 movement and as mentioned above the dial and hands you have would not fit either.
Even some of the truly high end reps cannot have a 3135 placed into them. We are not trying to be mean but the watch in the photos above is not a high end rep, from dial to SEL's to the movement inside all indicate a run of the mill one and it will almost certainly NOT fit a 3135. Just the diameter and height differences alone already show the issue you would face. The 3135 is wider and taller than the DG movement.
If you are set on wanting a watch with a 3135 I would recommend you purchasing one of the new JF factory sub reps with the cone 3135 already inside and then if you want to swap for Gen its will truly be a simple swap and you would get to keep the dial and hands.
To answer what exactly the movement you have it appears to be a Chinese DG2803. See the photo below for comparison.
Chinese Automatic Movement DG2803
Ligne size 11.5, height 5.3, hand sizes 1.00/1.52/.17, functions: Day, Date, hour, minute, sweep.
Compare these specs to the 3135
28.50 mm(12½ lignes)
in diameter, 6.00 mm - height