Piecing together an A/C system

Thanks Bill, great information! There is a local company that specializes in all sorts of A/C systems not just cars (I try to avoid automotive A/C shops as most technicians there only have a very basic knowledge of A/C systems) but I haven't been able to get ahold of them since they are so busy (apparently they only have 2-3 employees and the office is only open when they are not working on something).
Regarding fittings I plan on using Manuli Frigoclic (comparable to Aeroquip E-Z A/C fittings but available locally) - and their hoses:

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