I wouldn't say toyota u-joints are amazingly strong. They are a bit smaller than a 1310 and comparable in strength. What they do have going for them is that the yokes are set up to allow a ton of angularity... over 30 degrees in most cases. If you've got the stock toyota 4-banger in there, and aren't running crazy low range reduction, they should work fine. And yes, Jesse from high angle driveline does make a nice flange to mate the stock toyota driveshaft to a D60.
One thing to bear in mind is that they used different patterns on the toyota flanges with different bolt spacing and size over the years. The later ones with the larger bolts & spacing are preferable. If you have the early small stuff, you'll might need to swap over to the later model flange on your driveshaft to match the bolt pattern on the high angle yoke.
