What I discuss if for when you put the 1.9TD and intercooler in.
When I built my Caddy upgrade, I found I simply was geared too low with the 020 FF. I used an ASF with .071 OD, and with 13" rims it revved like an old gasser truck. I then put 15" tires on. 195/55-15. I used the 210mm clutch and the only real mod needed was a speedometer converter. The ASF has 3:67 and while the .71 OD made a minor difference, the tire size brought it around. I have carried more loads on my caddy, than I am pretty sure anyone on this forum, with no rubbing issues.
As for power, I recently made a trip with an EMPTY 500 gallon fuel tank in the bed of my caddy. I was running cruise control in VA grades, 10-15% and while my cruise will NEVER droop empty, I was drooping @ 5 mph in 5th. I have yet to aftercool, and I have my boost limited to 6psi. This was a 130 mile trip loaded, and is on the well on the outside margins of loads that should be transported in a caddy.
I am a farmer, and my little caddy is my commuter daily driver, to a real job, as you can't make a living as a small farmer, and when the opportunity to pick up feed, tools, farm implements arise, if it fits, the caddy is the first choice. I have owned my little caddy since 1992, and brought it from TX across the US during my miltary career, and took it from its original 1.6 whopping 48-52HP where in flat ground, turning on AC was a jake-brake, and where cruise control was to the floor, and max speed was low 70s, to now, pulling cruise any speed above 35 in 5th, and top speed is registered only by Garmin. I backed off a 100mph. I pull 85-90 on interstate on cruise. Since I routinely run freeways speeds at 70-75, and became tired of my coolant gage laying over to the right, installed a Griffin Schirroco race radiator, double pass radiator, and let me just say she runs cool.
No problems with the 020, or the clutch. While I don't rip around like a drag racer, I run hard, and carry some fairly heavy loads. Wish you luck on your little pickup.
Wayne, south central VA