Last night, I went ahead and bought an ESC and a new battery. The ESC was quite a bit cheaper than I was expecting at only $30. I got a new battery because it was a NiMH (Nickel-metal Hydrite) and had a much bigger capacity 3000mAh (milliAmp Hours) over my old NiCd battery with only 1200mAh although they had batteries with capacities up to 5000mAh. I also discovered a hidden battery compartment for the old circuitry that could hold 4 AA batteries, although I don't currently need it. I may make use of that if I feel it could be beneficial to any additional circuitry. The ESC was able to provide power to the receiver as well as the servo, so that was a definite bonus since I won't need the AA battery pack that came with the receiver. Also, it looks like the ESC has very low resistance and a small footprint, so I see little benefit in building one myself.

I went ahead and soldered 2 wires together inside and insulated it with heat shrink tubing that I had bought and then secured the receiver inside with some velcro. Then I desoldered the switch from the ESC and soldered a bigger one that came with the car so it would fit inside the switch compartment. Then I straightened out a bend in one of the front tie rods (probably from the previous owner) and reattached the front bumper. At this point, I need to buy some bullet connectors, heavier gauge wire and some method of securing the battery compartment door since the tabs have been worn down over time. I figure I can use velcro for that. I'll head over to Radioshack later today to get those items (they should have all of those things) and then I can finish assembling the car tonight and recalibrate the steering so that I can at least get it running as a basic RC vehicle, which is excellent for the summertime.

I also was looking into the costs for a real ICD and what a development board would cost and the prices seem more reasonable to me--especially on ebay. I may get those eventually if I can't get my ICD clone working.