How long are the spacers for mounting studs? It seems every delux heater I have had out never had them. One used wood!
I never measured so this is a best guess; 5 @ 1/2"ea. & 1 @ 3/4". Exact is not probably critical but you'll know when you put in the fan/fresh air diverter because they space the unit off the firewall and the air intake lines up with the vent flange.
For the one that is longer you can figure it out as it compensates for the firewall offset from the other two which is not much.
Thin wall aluminum or copper tubing will do it, 1/2"OD max. And they were not snug around the stud.
