You reckon they would fade well? One is a candy and the other is a flat colour right?
I’d be tempted to do a fairly basic masked transition from one to the other with a black outline. Maroon from the front. Couple of ‘escaping’ outlined maroon bits towards the back of the shell
For the next shell planning a gunmetal to maroon sick fade. But which way round? Gunmetal or maroon at the front?