A lot of extra cost goes in with it. Update fuel pump system with fuel return. That's pump, tank, plumbing, filters, etc. A dry place for the computer. Reprogramming the prom if you delete some of the sub-systems. Sensor wiring to run. Some fabricating ( adding an O2 bung, etc.)
I'm in the middle of installing a tuned port in my 'Burb and I still have a ways to go!
