I have an alcove in a wall which is to house the new hifi unit. The wall is solid block. I was going to build a unit that I could pull out to get to the back but I'm worried about the sonic and aesthetic effects of coasters! So, while reading hifi news last night I hit an idea. How about fix MDF shleves to the wall on one of those adjustable shelf systems and build a false cabinet around it that can easilly be lifted away to give me side access to the gear and cabling? Sounds good but I'm wondering where I could get a shelf system strong enough to hold a heavy power amp. Any ideas?