Shouldn't you be studying for the boards or did you take them already?
Are you planning on having these welded on or making them bolt on? I like them bolted on because if need be they can come for whatever reason. For me, it's easier to work on them when they are off the vehicle. We had made my set, Rob's, Kenton's and Andre's back when we had our slider build at Todd's last year. I still plan on tapping them to make them air tanks for when I get around to my OBA system. After seeing Al's, I liked his setup too. Back to the point, It looks like the 4xInnovations are straight weld on. I'm not saying that this is a bad thing, but for me I like the idea of a bolt on. If you ever have to repaint or fix a dent or a straighten an outrigger leg or something, it would be easier to do a bench repair than having to fix it on your back.
Another thing to think of is that your measurements better be exact and the builds are identical for both sides. Kenton's and mine are the same design and we used the same measurements, but he had to bend his pinch welds a little to get them to mount straight and I didn't. It would suck for you to measure everything and then go have them installed and they didn't fit right. I know the can be easily fixed, but it depends on how flexible you are with your time. You said you can only get out there once so I hope they fit right the first time. Judging by the pics of their slider designs on the site, it looks to be top notch stuff.
Have you looked around locally to see if anyone can fab up some sliders for you here? I'm guessing it might cost around the same but at least you know the end products will fit your rig exactly.
I haven't finished Alen's yet because I haven't had his 80 lately to mock them up to before finish welding. They are a tight enough fit that it's best to have all the parts made, then tweak them to fit exactly to the truck.
Weld on suck. You need to be able to take them off once in a while.
If you guys had real cruisers like my , they would have captured nuts in the frame where it was designed for factory sliders.