Yes The B-24 Guy also did F4F-3. I did the FM-2 from the stock model. The FM-1 was the same as the F4F-4 but for a loss of two .50 cals on the later models. The early FM-1s where the same as the F4F-4 and later ones changed from six .50 cals to four .50 cals like the F4F-3 had.
The F4F line brakes down like this.
F4F-3: four .50 cals and no drop/bombs.
F4F-4: Added support for bombs and drop tanks and added two .50 cals
FM-1: Same as F4F-4 with later models having two .50 cals removed. Rocket mounts added for early and later models.
FM-2: four .50 cals like later FM-1. Engine was changed from the 1,200 HP Pratt & Whitney R-1830 to a 1,200HP/,1,350 HP using WEP Wright R-1820 and a taller tail to cope with the torque on take off from small CVE using WEP.