I believe that the calculation and #2 point would be OK if the two engineers for calculation would be the same persons also for electrical part of mechanical design. Actually we can make these steps just after the calculation is made so the two engineers can stay a week (or two) longer to see also this part of design.
It is #1 point that perhaps would be OK if somebody from mechanical engineering will come to see how we do these steps. He/she can come after the calculation is being made. Between calculation and making of documentation of tank and accessories there are some steps that needs to be performed. These steps are: