You could use a rostra cruise control system (
www.rostra.com) and install it for $300 ish..
the cruise control module is < $200...
for the control you can add a lever mount or use the Rf module (buttons go on the side of the steering wheel)
either of these cruise modules work.. (one is vacuum the other is all electric.. which most people feel is better)
Part # 250-1176
Part # 250-1223
For the controls you can use any of these part #'s Control Lever: 250-3421,250-3125,250-3742 The controls range from $50-$80 depending on which one you get...
they don't list you needing a throttle adapter but you could call them and ask.
Even SummitRacing carries the cruise control and the controls
Here are the pins you need to know to hook it up...
VSS Wire: Loc 12 Pos 58 of 104 Pin Conn
VSS Wire Color: Gray/Black
VSS Pulse: 8000
VSS Tach Wire: Loc 12 Pos 48 of 104 Pin Conn
Tach Signal Wire Color: White/Pink
Brake Switch Positive: Green/Red
Brake Switch Negative: GREEN
To translate the location #'s from above to where they are on the car.. use this .pdf..
http://www.rostra.com/pdf/wirelocations.pdf
A friend of mine used to work at a speedometer shop which is how I know about this cruise control...
I'm actually getting ready to install one on my new to me Honda (new Daily Driver)..
~Mark