I have done similar, the only issue is the residual mineral oil wants to be under 5%, as most of the oil is in the compressor you will be well on your way by changing the condensing unit. The compressor would benefit from an oil change once the system has run a few hours, so you may like to think about piping arrangements to make draining the oil easier.

If it is a chiller and not a freezer then you might like to consider R134a instead of R404A due to its lower gwp and its less likely to get banned or highly taxed like there is talk of doing with the high gwp refrigerants.