[mike knight]

my experience with installing a turbo in an spf may be of interest. i have a 351 windsor with a 93mm intercooled turbo. i actually bought 2 56 mm turbos as that was my intent. we could not lay up a plumbing system for the intercooler and turbos in the engine compartment. we had made arrangements with the supplier to return the turbos if we couldn't succeed. there simply wasn't enough space for all of that 3" piping and intercoolers. i even went to an electric radiator mount water pump. after a considerable amount of work we decided to go with the single turbo.
i have also experienced cooling issues. my car in traffic on a hot summer day wants to run over 105 c, about 220 f, and would probably continue to climb slowly. on the highway it runs perfect at about 180f. more work to be done with the cooling system over the winter. you can see a couple of pics of my installation in my gallery. i know you are asking about turbo installs for a 385. i can only imagine you might have the same issues as i with my small block, only compounded by the size of your motor and exhaust system.
i will say that performance with the turbo at about 30 lbs of boost is insane. i am driving on the street with about 7 lbs of boost and acceleration is very quick. in third at 60 mph if you stand on it the rear 295's break loose. at 140mph in 6th it pulls hard. turbo whine is very pronounced. mustang dyno with 7 lbs of boost equals 596 rwhp 4800 rpm and 613 ft lbs at 4250 rpm.
incidentally what you see in my pics was expensive. fyi