nuvi54 JCV files for sd

Hello I will like to fix nuvi54 on sd card for maps 2017-10 I loaded the img files but I dont know which JCV files do I need since the old one I have on my nuvi is D3478080A and I don't find files starting with D34780??A.JCV is it replace by a new file sequence
By the way will a gmapprom.img and JCV fiels on an sd card will work on nuvi54
thanks