For what little its worth the only header i can think of that is 1 3/4 stepped to 1 7/8 is a Hedman multipiece header that last i checked was proably 7-800dollars,so they are a fairly expensive starter kit even thougth they do have a few qualitys that makes them more probable to have some kind of usefullness as a starting kit to build from on a early A than any other late A header i can think of.
Personaly i would probably prefer doing a header with atelast two tubes on each side going out thru the fenderwell and then in under the framerail again if i where to build something similar on a early A.
