Upgrading RAM and HD space on ibm F50

I am in the process of deciding whether to upgrade my IBM F50 server myself or spend too much money getting it done by a tech. The only issue I face is that I have heard that RISC6000 machines sometimes like to have ram placed in specific slots. Can anyone tell me if this is the case? If it isn’t, and I can go ahead and install this myself. As well, any advice on hard drive upgrades will be extremely helpful, and rewarded.