heater hose restrictor goes in the heater core supply hose, think it will only fit that one. Is it a black restrictor? Usually the tapered part faces the heater core and the flat part faces the water pump direction. The restrictors don't come with instructions so I googled and found some info about them.
Dart 363, TFS 205 TW heads, ported RPM II intake, FTI blower cam, MSD dist and 6AL, 80lb inj, Glenns Perf rails, DISC Procharger 13#, Sheetmetal intercooler, Stinger computer, BBK longtubes, 3 inch LX exhaust, TKO 600, RAM Powergrip HD, 3:73 with Eaton posi, Strange 31 sp., Eibach drag launch springs, MM adj lower rear arms. 586 RWHP without tune (tune coming very soon)