Hi, Prof
Warm welcome to MBM and the build
In answer to a very first question - to fill holes in ABS you can make an ABS filler goop using a small airtight pot - glass or similar and chucking into it a load of cut-up bits of the ABS (trimmings, sprue bits) and putting in a dollop of the solvent plastic glue*. Seal and leave overnight and you will have a more-or less runny liquid plastic. Apply and leave to dry and it becomes an integral part of the ABS
*like Polyweld or MEK**
**Methyl ethyl Ketone
Note - it also works with styrene, but not foam polystyrene!
Looking forward to the build. I hope the plethora of adhesive advice has not left you up a gum tree.
(sorry)
andrew