more white space issues

[modchipfitters.co.uk]

i have just about got my layout how i want it but i have 2 main problems

1,

i have a white space just above my center box heading bars when i view the site in firefox but they arent there in internet explorer but in internet explorer i have white spaces on either side of my center box heading bars see pics below so u can understand what i meen

i have tried everything to get rid of theses spaces from changing padding to changing the image sizxe but nothing make any difference

and

2,

i cant seem to get any spacinf between the side boxxes. what i want is say 5-10px white space from the foooter of 1 siade box to the header of the next side box so they are no longer touching each other and again ive tried usinf padding in the css file but it doesnt change anything

any help much appreciated

[modchipfitters.co.uk]

anyone got any idea's at all???