Thanks to all those who offered advice for the AC system repair that I was contemplating a few weeks back. I'm happy to report that this is now complete and working perfectly. 
The details - '87 Westy with AC not blowing cold anymore. Leak check revealed multiple leaks in the various hoses. I pulled all the old hoses and had them rebuilt. Reinstalled them with a new drier/receiver and then had the system pumped down, recharged and fully leak checked. 'Held vacuum like a champ' & 'not even one tiny leak detected' were the reports from the AC specialist. After 2 weeks�of daily use (& 1000 miles) including CA central valley temperatures, I can report that the system puts out icy cold air and beats the 100F heat down�into the 70's inside easily on 1 or 2 fan settings�(even at highway speeds where plenty of air is leaking into the cab area through the worn-out heater seals).�I can thoroughly recommend Mark at San Carlos Auto Radiator & AC ((650) 593-3193) who was flexible enough to do just part of the job (rebuilding the hoses, recharging & leak testing the system) and most importantly, gave loads of free advice on getting the
 old hoses out and new ones in. I just had to do the labor intensive part of the job, but that meant my total bill was reasonable ($630). After considering freon alternatives, I stuck with R12, as this gives the best cooling without going to exotic coolants and since the system is now solid again, it shouldn't leak out into the atmosphere too soon.
Mike 
'87 Westy