This is the 18" silent run solid mount fan we ended up with on the 440.
Note it is close to the radiator, 3/4"
You put the bolts through the fan and spacer, then you can slip it in and mount It to the water pump.
I used a rubber tipped porto-power to flex the core support forward just a tad, pushing off the block.
Started the bolts and snugged them up, then let the pressure off the port-power to return to the original position. No shroud used on the 440 application. Fans available on ebay.
Slant 6 fan spacer might be close to what you need for your setup.