Ford Ranger Wiring / Fusing Questions

I am wanting to do the "Radio on until door open" setup and I also want to install an alarm.

Can I run both off the same +12V connection with 1 30A fuse?  Or is that too much current draw?  Alarm is a Crime Guard 745i3 with a bunch of sensors.

Can both be grounded to the same place?

Also does the 2003 Ford Ranger GEM do the thing with pulsing voltage making alarms think doors open when they are not?  Any way to test this without waiting 40 min or however long it usually takes to start pulsing?

With the "Radio on until door open" two relay setup does the radio work with the door open and the key in the accessory position? Or do I need the 3 relay setup for that?  If the key in is accessory does radio work when door closed, opened, then closed again?

Radio On Until Door Opened

• You can use the same power source for both applications.
• Both can be grounded in the same palce as well
• Your Ford has the GEM
• Yes it will still work because it is breaking the power to the IGN wire, regardless of power source.