Here's a link to a thread I started last year. I have the OBX on my '76 and went through what you've described. For the money they are worth it. You may have to modify the rocker covers, to what degree depends on your car and how good the body mounts are. Pretty straight forward installation however the bolts holes to the cylinder heads aren't perfect. I had to enlarge one hole on each side in order to get the second bolt in.
Good luck
http://www.smokinvette.com/corvetteforum/showthread.php?t=54939
Eric
.
Good luck
http://www.smokinvette.com/corvetteforum/showthread.php?t=54939
Eric
.