I can tell you exactly what I would do, and have been looking for a truck to do it with!! Bear with me....I have a 49 Chevy Fleetline Deluxe car that my wifes great grandfather bought new. Last on the road in 1970, and has all the stainless trim and doors shut like a bank vault. Minimal rust, but the family wanted to have it hauled away from the old homeplace. I jumped at the chance to grab it. Factory engine was a straight six, 216 cu. These engines had "babbit bearings", which are poured bearings and make this engine basically far too cost prohibitive to rebuild. So, I lucked into a 56 235 straight 6 from a one owner family 56 pickup to go in the 49. But, I want the 49 to be a driver, and the 235 isn't all that powerful and can't be built to be. So, still wanting to be different than the V8 SBC crowd, I got a Chevy straight 6 292 for it. So now, I have this great low mileage 235 inline six - can ya tell I just love these old straight sixes?
There's one guy on an S10 forum that did exactly this - put an old straight 6 into an S10, and that's what I wanna do. Lightweight truck, reliable and basic straight 6 with plenty of torque to move it along nicely. Also have a T5 to put behind it, which obviously fits nicely with the idea of finding an S10 manual truck for the swap. Won't be like that same ole thing everybody else does with a SBC. Neat lil daily driver or fun around town truck, be fun to take to a car show and freak folks out.
So, if you decide not to build it - which I am NOT trying to talk you out of doing, don't trash it!!!! Call me and I'll be on the way from Bham AL with a trailer!!