Great idea. I guess you will be doing this on a budget? If you want some ideas, I have been going through the old mods done over on overclock.net and there are some that mod the Dell (or similar Dell). I will see if I can find them for you.
About the front panel, I am in a similar boat. A mod I have been doing involves removing the OEM front panel because it sticks out an inch and interferes with my added front intake. My plan is to pick up acrylic sheet from Home depot and install it over the front with machine screws. There will be a 120mm hole for intake with some large hole mesh (for protection of wandering fingers). I estimate that it will cost me $15-$20 for parts and tools to do that.
Anyway, you say you want to keep the original plate, so can we get some shots of that panel taken off the machine? You might be able to cut a hole on the black plastic and leave the gray upper plastic intact.
Somewhat of a budget, yeah. At least, for the time being. Mostly right now though, I'm focused on acquiring the parts I need to make the mods happen. That means all the necessary stuff to make the mobo function properly. Fortunately, I didn't have to do anything crazy with the motherboard standoffs in the case. It lined up pretty much perfectly for my motherboard.
As far as keeping the original plate— not necessarily. I could keep it and modify it. But if I did, I'd have to figure out how to work with the aesthetics of the case, as it were.
I'm thinking along similar lines as to your comment on picking up acrylic sheet. I may have to go with a colored acrylic sheet. Black and maybe frosted white or grey if I can find 'em. To the Google™! That said, acrylic or some form of metal. The only potential issue is needing to figure out how to handle the tabs that holds the faceplate in. Maybe I should forego the tabs and make it pop-rivet or screwable to make it easier for me to remove the faceplate in future. Which means at some point I should find a Dell logo or get a machined Dell logo, something like that and a nice LED switch for it. I'll have to see if I can't yoink the power button off the faceplate. I have to admit I do like that thing.
As for the pic of the faceplate and all, I'll get to doing that ASAP.