I know the M4A3 and M4A1 76mm come with the late FDA cover (sharp nose) but I’m not certain it’s included in the M4 or M4 hybrid kits. I’m hoping that I’m mistaken because the hybrid was a late production vehicle and I’m not sure I’ve ever seen photos of them with the round cast FDA cover. Also the late hull in the M4 kit would require a late cover as well.
Considering the scope of the subject, I think Rubicon Models did a great job, but yes, not every little aspect and detail is covered in any one kit. Sometimes you have to mix and match, and in rare cases you might have to improvise.
I’m fairly new here, perhaps Rubicon has addressed this? Will a resin FDA become available to purchase seperately?
Maybe, but considering all the projects on their workbench, it wouldn't be anytime soon.
Basically, there is a shortage of sharp nose FDA, the only kit that could be a donor is the M4A2 76mm if you build it as a 75mm tank with the early hull and then take the late FDA for another kits.
Not a perfect solution, but one of the things people can do is take the part from the M4A3 kit and make a resin copy.
Yes, a lot of modellers that are gamers will tell you that this is easy to do, and I have done this with other plastic and metal parts. I wouldn't call the process easy though, but for sure very doable.