My MSD inline fuel pump is extremely loud. I'm thinking of mounting it witrh better cushioning and possibly putting it inside a plastic box with some foam. I haven't run it for an extended time yet, do they get hot? Can I mount it inside a box?

In line pumps do run much louder than in tank pumps, this is why OEM's put the pump in the tank. It quiets and cools, put it in a box and expect early failure.

Look at the 88? Ford trucks, they have there in a foam sleeve and rubber isolators to keep the noise from coming up the frame.

I run a Walbro inline pump and it's very quiet. It's been running two years now in a DD EFI Blazer with no problems...so it seams to be pretty reliable.

I should also add it runs cool as well.