Coolant flow questions

[spectrum]

I've got a '91 Suburban 4x4 with the 6.2L, and need to know where to tap into the coolant lines in order to install a rear heater core. I want to be sure I get good coolant flow down the new loop, but am not sure where the hi/low pressure spots are.

Thanks in advance,
Andy

[86burb]

You should be able to pick up the complete assembly at a wrecker for a reasonable amount.
The factory rear aux heater is the same for 82-91 gas or diesel. This will get you the original dash switch, aux heater water shutoff valve, coolant lines, blower motor, heater core, and brackets + factory look (which is always nice).