Help with Installation

So I finally brought the MPC1k out of the box. Its the black casing with the crappy pads.

I've got, in transit, the following:

-MPC Pad Upgrade kit
-128mb RAM upgrade
-120gb Hard drive kit

I have been doing tons of research but its hard to get the straightest answer without posting in forums such as these.

My questions.....

I plan to have JJ OS running, and I want to know, which is the Version I should install first? (3.08, 4.99) and do I install/upgrade to the new OS before or after installing all new upgrades ( Pad kit, Hard drive, RAM)

I would like to play around with JJ OS before I receive all the parts.

Do a little search on youtube, there are videos for your Pad, HD and RAM Upgrade.

Thanks.

But is it recommended to install all the Pads, HD and RAM with the AKAI OS still present? Will i run into problems if I Have JJOS installed then upgrade the RAM, HD and Pads?