New coil has lower resistance in primary so will draw more current, although I think that when connected to power it is also effected by the inductance.
I would stay with the old one and keep the new one as a spare.
We saw in the FSM that 3.0 amps was for when the engine was off, points closed.
1.9 amps running at idle (500 - 600 rpm?) So you can do the votlage drop math for that if you want.