348 header heat shields

Been there, done that a bunch of times. Check out my site to see some pics of the work.
To the DYI'ers out there, I'll spill a few hard fought bits of knowledge.
Take care not to breathe the fiber insulation dust. I doubt it is asbestos, but as we recall asbstos was once considered very safe.
And here is the "best bang for the buck" on the aluminum: a set of pruning shears, best if gotten at a garage sale, will not only cut well but follows corners rather nicely. Much easier and less of the dust in the air to deal with.
Whatever shop does the headers should make sure to clean the insides well. I developed a "Roto Rooter" kind of tool for this as it is not possible to blast around corners. With the inside and outside done, you can expect a 50% drop in engine compartment heat! And a bonus is by coating the insides well, it dramatically cuts the header tube metal from heat as well, so cracks are not near the problem.
HTH my friend!
Kermit

 

Glad to help, that is what it is about.
My site is:
www.durable1.com
Oh yeah, I have found that the Garage sale pruning shears are usually older, and a heck of a lot better made!
Kermit