Sorry dude, was out on lunch
you want to set up 1 maybe 2 viewports and use a smaller scale. For example, if your elevation is at 1:20, the details really wana be at 1:10. The next problem you will have is making sure your dims are the right size at that scale. For example, using the same dimension and text size for all your details will mean the smaller scale viewports will show the text and dims larger than those on the elevation(s).
What you wana do is copy the 'standard' dim style and call it 1_10 (colons arent allowed for some reason) then you are given the option to change the settings of the dim style (font type, size, arrow size/shape ect etc) There is also an option to scale the the size of the dimension by a factor. The standard dim style is drawing at 1:1 in model space (or 0.1) you wont to make sure this dim style (the one you called 1_10) is half the original scale, for example 0.5.
Then when puting your dims and leaders on the text and overall scale in paper space will match that of the 1:20 viewport even tho the actual model scale is smaller.
I apologies if this is difficult to understand, its kinda difficult to explain something I do without even realising it