Funny you ask about these steps, I have them custom mounted on my '05 AC Tundra. I had to custom mount them because they don't make a step system for the AccessCab Tundra.
The mounting plates are in different positions for different model trucks. For instance, see this photo:

The holes and the length of the bracket with the 3 cirlce holes in it may be different for the Taco
vs the 4runner
vs the Tundra. I have noticed that underneath my Tundra, the positions it was to mount onto were simply not there. see this photo of where the stock holes were supposed to be:

It was like I was missing 5 holes! I then had to drill 1/2 holes in the running boards area under the cab, lodge in some 8mm nutserts and rivet them in there. Now I have 6 running board nuts riveted in the right spots.
New holes and associated nutserts:

I can give you the dimensions of the mounting brackets for the part# T0678QC as seen
HERE. Maybe that will help you see if the mounting points are in the right spots.
Here's the step:


exact measurements:
front bracket to middle bracket:
30"
middle bracket to rear bracket:
26"
total bar length:
85"
front of bar to 1st step:
9"
rear of 1st step to front of 2nd step:
13"
largest bolt you can fit through the mounting holes:
3/8" or
8mm
Here's the finished product:

I'm pretty happy with them. I will have new tabs welded to the cab so I can better support them. I may even just have the bars welded at some point. But I'd like to get them line-x'd first.

That's another thread though...
