Neither the Bonneville or the TranSport ever make the 1/4 mark unless approaching 200F. 180F is just like the picture above shows, just under the 1/4 mark.
Guage is decidedly non-linear. Bottom line seems to be 100F, 1/4 is 190-200, 1/2 (straight up) is 220 and full is 260F (think red line is 250F). GM seems to feel that everything is OK at 220-230F.
Anything over 150F should produce decent heat but GM guages are so notoriously inaccurate that the only way to know what the ECM thinks the coolant temperature is with a scan tool.
Image is of 181F (is night so not clearest but if I use a flood or flash, the OTC 2000 display is invisible)