Heater box types

[ozbox]

i finally pulled finger and went and looked at my shelf of heater box housings for the engine bay side..i couldnt quite remember the differences but knew there was more than one type...
2 types of outer heater boxes.
1 has a resistor which a 3 pin wiring plug goes to which is hq
and 1 does not...which is hj hx hz wb..
2 types of heater cores with different size tubes going thru the outer box,1 has small and large and 1 has both same size..just change grommets to suit.
also fans differ because of wiring as above.

[HK1837]

Now you've jogged my memory. I knew the fans were different, but forgot about the resistors