As you would have been aware by now, there are some in-house rules in our website (not sure about the forums) above modifications of DS - replacing heavy vee bays for lights, BA for infantry, etc. While none of the MHB brokers have ever gone on to check, it was with the understanding that MUCOs practise common sense in that you wouldn't be modifying your DropShip(s) after every mission and/or after every contract.
We've always prided ourselves as being able to keep things logical and feasible, so do practice common sense.
Finally, keep safe and keep healthy all!