So one problem with the Volvo is the radiator fan.
It's a direct mechanical link (non-clutch!) off of the water pump, on a 2 foot prop-shaft from the mid-mounted engine out to the radiator up front, on two rubber flexible "universal" joints.
This causes a few problems.
#1: it has problems cooling the engine at idle. Particularly a problem with Denver having a week of 105 degree days lately.
#2: the "universal" joints rob a lot of power from the engine.
#3: it makes an immense amount of noise in the cab. At speed, you have to shout in order to converse in the cab.
Time for a change.

Off with the grill

And the wire mesh behind it

there's the radiator.

Opening up the panels to access the radiator from the top,

Radiator and it's fabric shroud removed, after dismantling several frame crossmembers and bumper reinforcements.

The fan. It's an asymmetrical design.

Very asymmetrical.

Fan-on-a-stick out.
New fan is a Flex-a-lite 15" 24v variable speed fan. it comes with a large shroud to direct airflow, however the shroud is about 2 inches too wide for the radiator tunnel. We removed the gasket material along the outside, cut it down on the mill and trimmed part of a corner with a dremmel to fit a series of power cable packs on the upper left corner, and then replaced the gasket material around the cuts we made save for the left side. (No photos of installation, at this point it was late in the day, very hot, and we just forgot), installation required squeezing the fan past two locator ribs (left and right) behind where the radiator sits. We did this by not re-adding the fan gasket to the left side of the fan shroud where we made the cut. this allowed us to squeeze it past the ribs by inserting the right side first, then pushing the left side in following it, and then pulling both sides back to straighten it out. we then fully sealed it by attaching the gasket material to the left side rib - wound up working flawlessly.
Wiring took some splicing that we'll go back and fix at a later date (major electrical system install coming up next anyways) as the wires flex-a-lite provided didn't anticipate a mid-engined vehicle and were about 2 feet short.
Probe for the fan was inserted into the radiator and epoxied in place with a high temperature sensor-safe epoxy (couldn't go all the way through as flex-a-lite reccomends, Volvo used an offset rib design, so the set behind the first was offset to allow maximum surface area, couldn't push the probe through all the way).
Stationary tests show a dramatic increase in airflow and cooling capability, as well as a dramatic lowering of noise in the cab. was too late to make a test drive yesterday but we expect to see a noticable increase in available engine power as well.
The Volvo keeps coming along!