Just wanted to chime in my 25 years of LUV experience here too. The LUV frame is fully boxed, a solid square tube, not an open C shape like the S10. I'd say strength wise the LUV would be near twice as strong if not more. I'd also ask better suspension in what way? The stock torsion bar front suspension on a LUV handles quite nicely for a small truck. The rear end could use a little work to help traction and wheel hop if you really have some power to work with, but very easy to mod and upgrade. Unless you are trying to build a drag truck, basic leaf sprung rear is going to out perform the rest of the truck with its light rear end anyway. I've seen a stock 77 take 25 MPH corners at 80+, and even the rear end held on to the pavement.
The biggest thing I see is all the fabrication work needed to mount a LUV on the S10 frame. Length and width are different, and not one single cab mount will be in the right place. By the time you get done welding mounts on the frame, you will have done much more work than it takes to mod the stock frame. If you are looking for options to drop it to the ground, air bags, and 5 lugs, then I think there are easier solutions to all of those problems without downgrading frame strength.
Sure there are more bolt-em-on-and-run parts for the S10 frame and suspension, but a LUV body is REALLY not just bolt it on. Its a lot of work.
Here is what I'd go for with what you've got and what you want. 5 lug rear, S10 axle would work depending on the size of motor you go with. Get your front hubs drilled out for 5 lugs, there is a guy on here that will do it and include the studs. Then either lower the front using the torsions, or convert it to coilovers. There are several builds here that have done it. If you are really wanting to get extreme, 4 link the rear and cut the frame to tuck the rear axle, air bags and controller, and really sit it on the ground.
Not much I can say about the longbed vs short. An S10 frame will not match up wheel openings to a short bed LUV cab and bed though. Personally, I like the long bed look if you are going for low low. It just makes it look that much lower being long too.
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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)
MEPR: Man, my 4x4 makes all other LUVs look good
