Will a set of headers that fit a 77 work on a 78 with no problems?

Most headers for Elcos usually swap between years. Check catalog part numbers. They list headers that fit from 64 to 88 same part number. I know I had a set of headers on my '67 Elco and I switched them over to my '81 Elco with no problems.

Hedman lists the part numbers as different, but I can't say they wouldn't fit...keep us posted if you try it and it works and what kind you used!