You are correct, this is the very truck that use to cruise the streets of Pullman many years ago! Plan to get my wsu sticker on the back soon.....
I measured the top of the truck and it's at about 81-1/2" to 82" tall. My garage is 83" tall so it fits. Strangely, I think I measured 81-1/2" on the 37" tires?!? Maybe the difference is "remaining tread" on each set of tires.
Anyways, the blazer with the 4" lift fits in two garage spaces (two houses) and also my work parking garage. Can't believe it really.
As far as the lift, I don't know a whole lot about it. 4" was figured by measuring a stock blazer I found from the axle hub to the bottom lip of the fender. Mine measured 4" more so that's why I assume 4" lift.
I doubt the driveline was lengthened or any transfer case drop was done. I do get a little vibration and it may be from the driveline angle. I do know the kid before put in new u-joints so obviously, the lift and tires are not too kind in those areas for wear.
I have no idea on the brand name either (for the lift). But I do know it's a LOT bouncier than stock. It may be just the springs.....I don't know. Perhaps softride springs would help. I'm still debating about going down to 33's and a 2-1/2" lift. But for now, at least I can turn into driveways without the 37" tires rubbing the fenders.
The BFG's are great tires too. Definitely recommend.
Good luck!