I'm concerned that it started spitting after only 10 minutes. I'm assuming the stat sat for those years. I would take out the stat & do for a drive & holler back & working the stat w your hands to see if it's free and no stat for a few minutes of driving is not going to hurt things from a delayed warmup. I would also drill a ~1/16" hole in the flat of it for easier fillup & lets air pockets out & takes 2 minutes to do & no down sides. EDIT I'm assuming the timing/shroud/fan/fan distance are acceptable