I think with a little paint it will look the part . These kits are small enough , you don't have to go all scale scratch build unless your really crazy Shep Paine , the guy who built all those awesome 1/32 Monogram tank model dioramas ( and 1/48 wingy things ) back in the 70s had the right idea , just use what ever looks the part , the human eye will fill in most of the missing details and over look things that under careful scuitany would stand out . For example he used Airfix wagon wheels as fans on his Panzer IV , took me 20 years the realize they ere the wrong shape
And I've got books with pictures of Panzer IV engine compartments , it was just so cool you thought it "looked" right . Those family and friends who look at your " toy " collection wouldn't know what the vehicle is never mind the extra detail you added to it . In fact a lot of model tank builders probably wouldn't know what improvements you've made to the kit unless they've actually built one themselves . I couldn't tell you if the shape of your breach guard is correct , I'm not up on the Hellcat , but I would know that it was missing because all tank guns have a guard of some sort to protect the crew . I've added some to my Panzer 3 , 4 with open turret side doors , as well to my 1941 T-34s because its what you see when you look in the hatch . Are they the right size and shape , no but they look the part which is good enough for me . Same can be said for the internal details on the turret side doors , its not exact but looks the part