Here you are an enlarged part of the pic with the bottom front plate seen a little bit better.
For the filling of the wee apperture you may use either a dissolved putty ( MRHobby one ) or epoxy putty ( Tamiya one ). The option for both of them can be a mixture of the talc powder and some of a light grey paint or a CA glue.
Thanks my friend....
....and what a difference from that SU-76M, mind you though....I'm looking forward to try their, Miniarts, new SU-122, light years better by the looks of it!
The only hiccups has been me dropping parts on the floor, find them....only to drop them again within 10 seconds of finding them!
Thinking of getting some other tracks for them, to get the right sag on them, not sure yet....quite enjoyable kit actually, even with a few errors in the instructions!
I think the SU-76M is also a quite nice kit. Just it requres some of experience with assembling of such kits. I have seen a couple of them made and must say they looked nice. Please pay your attention that the order of assembling you may find in a kit instruction can be incorrect and doesn't fit a modeller's skills.
I'll return to SU-76M at a later date....
The errors in Trumpeter's instructions was, if I remember correctly, mislabeled parts and showing them differently from how they actually are attached....