Masi13

In addition to changing the chainring, derailleurs, shifters, handlebar, and free wheel .... the original owner replaced the "Death Fork."

cinco

I'm fairly sure yours is an Aerospace Pro, possibly originally the version with clincher tires. The only differences between the three Aerospace models of that era were the derailleurs, seat, and (sort of) the paint and wheel size. The '76 catalog suggests that the Pro with tubulars was silver/blue, the Pro with clinchers was silver/black, and the GP was white/red, but having recently seen an original GP in white/blue I'm not sure I trust the catalog representation as much as I used to. Regardless, all the GPs seem to be white and all the Pros seem to be silver, so that combined with the other obvious Aerospace parts still on your bike suggest it to be a Pro. If the wheels are original you'll be able to tell which version - tubular or clincher, and only the Pro models got double-butted spokes. By the way, up until sometime in 1977 the original derailleurs would have been a Crane (Dura-Ace) in the rear and a Titlist (600) in the front on the Pro, versus a Titlist in the back and a Thunderbird in the front on the GP.

Masi13

Cinco .... Thanks for the added info. I'm gonna go with Aerospace Pro then!

Though it's now in something less than "all original" ..... Hopefully, given the bike's near perfect condition, I'll be able to pass it on to an interested party.

Cheers