Did they ever put a NP-203 in a early Blazer?

[ABLAZN]

I was looking at a 1971-72 Blazer that other day that I am considering buying. Someone has stuffed a 454 under the hood, but it looked like a Turbo 350/NP-203 transfer case combo behind it. I thought that all the Blazers of this vintage had the 205. then again, this might have been a 6 cylinder truck at one time also, if that makes a difference. I am thinking that it may have been a 4 speed originally because there was an after market floor shifter in it and not the column shift that I would expect to see with an auto. I have a couple of other engine/trans combo that I would like to put in it, but I was wondering if this was in any way original. This Blazer is nice enough that I would be willing to sell my current 1970 Blazer to get it.