Info on IM SD40-2 needed

[daniel_leavitt2000]

I'm writing up a large comparison between the SD40-2 available in N scale. I know the IM models have several versions available. I only have the Conrail version which is a mid-phase, large anti-climber version.

Without the other references handy, I need some info:

Were all high hoods only available in the early phase?
Did the early phase have the correct 81" nose, or did they use 88" noses for both?
Were there any other major detail changes between the two models?

Thanks!

[squirrelhunter]

I think they only tooled the 88" short hood, I think the review of the first run in Model Railroad News maybe?