Thanks for the reply!
That sounds good about soldering the wires to the stripboard.
Thanks for the advice about the MOSFETs as well.
I would like to check my understanding of something:
Looking at the datasheet for the MOSFETs I linked to previously (http://www.sparkfun.com/datasheets/Components/General/RFP30N06LE.pdf it looks to me that at Vgs = 5.0 V, the drain to source on-resistance is 0.047 ohms.
At 4A, the power dissipated would be I^2*R = 16 * 0.047 = 0.752 W. This is far below the 96 W maximum. So although the on-resistance may not be as low as more efficient MOSFETs, would it still be ok to use these?
I ask more out of a desire to understand rather than an insistence on using these particular MOSFETs. I don't really care which ones I use, it just seemed that these had a lower on-resistance at Vgs = 5V than normal MOSFETs.
Thanks again!