You might get better performance with 15F nozzles on the 1804s - 3 15F nozzles are going to draw over 11 gpm, so your mileage may vary.
I just finished a well system at 10gpm with pump pressure at 60 and house pressure 45.
I used RB 5004s with 2.0 nozzles. I used 4 heads per zone which at 35 PSI runs about 2gpm per head. So a total of 8gpm per zone. I didn't want to strain the well. I also calcuated the PSI lost down roughly to 35 PSI.
With the 1804s, I used the 12Hs. I factored about 1gpm at 35 PSI per head. I used 7-8 per zone.
Works very well. Until the well is established, I put a 5 minute delay between zones just to cover any loss.