First off YOU HAVE AN AWESOME SET-UP TO START WITH!! You already have the hard part done(the cleaning) so now comes the fun part!
For the lighting I think a T-Rex 160 watt flood MVB would work really well in your set-up. You just screw it right into your existing socket, and it provides all the light your RES needs!! I use two of the 100 watt floods, because they are so close to my basking spot, I think you should use the 160 watt flood one, because the basking spot will be so far away. After you screw it in, turn it on and let it warm up. A green spot should appear were the bulb is aimed. Right at that spot you should place your basking area(A large rock, or a piece of cork bark, or anything that you can come up with that would get your RES's ENTIRE shell out of the water.(so that it can fully dry off, preventing shell rot)).
Here is the link to the bulb, remember I think a 160 watt would be better in this case(I think you can find them cheaper elsewhere, but I don't feel like looking right now.)...
http://www.drsfostersmith.com/product/p ... 0836000000
For the filtration, I was going to say to get a canister filter, but I see that it is sunk into the floor(which is AWESOME!). So I guess you have to use a "in-the-water" filter. I think a pondmaster would be perfect for you! Here is the link, and you can pick out the one that would fit you pond(I think you can find them cheaper elsewhere, but I don't feel like looking right now.

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http://www.drsfostersmith.com/product/p ... catid=5232
Can't wait to see the updated pics!!
EDIT: Oh yeah I forgot! To heat the water you can just buy a couple of the Visi-therm stealth 250 watt heaters. They are grate!! Turtle smash prof!! And they don't turn on when it is warm out!! There on sale now for $16.00!!! To figure out how many you will need, measure the pond, and put the rough measurements into this calculator...
http://www.redearslider.com/calculator.html
Each heater will heat 60 gallons, so you may need you get a few!

Here is the link...
http://www.drsfostersmith.com/product/p ... atid=12060
I think thats it, feel free to ask any other questions you may have!!

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RES's
Tank, SCL 3.75in.
Diesel, SCL 3in.