I just finished a similar project. I found out that restoring an original FULL GAUGE cluster and adding a tach would cost at least 1100. for a professional job. And that was installing it myself. I opted to go with the dolphin gauges. Less than $400 including the panel and the gauges and I now have a tach. The only real hassle is combining your original fuel sending unit with theirs to make it work. I found the wiring much easier than I had originally anticipated.
