Have not cleaned any throttle body stuff, mainly cuz this motor ran like a dream when I took it out of the donor. Also, it runs like a dream once I get it started. It tends to "pop" not backfire ,pretty reliably during cranking This is what is so perplexing! I replaced coil today with no joy.
My cooling system is pretty hacked. Stainless lines run up in the general vicinity of the old heater vents. Metal has been cut for these on the undercarriage but they are tucked neatly. Lines run all the way to a Sirocco style radiator that has been mounted in a custom enclosure on the front. This is very un stock looking, but it is also dual purpose as it acts as a bike rack too. I bought the Bus this way. It had been previously fitted with a Toyota 3TC motor. While this motor was better than stock IMO it was still problematic, plus no one is stocking parts for these things anymore.
IMO I would not rely on a radiator setup that relies solely on active cooling. Get that radiator out front or fab a scoop if its underneath. Check this out for a clean install....(this is not mine, but me likey!)