89 Aerostar now runs cold

I have a 1989 aerostar van with 2.8? V6 I have had trouble from the time I got this van from another party who had tried to fix the rear heater. At any rate it has 110,000 kms on it and now runs very well after dumping transmission and simply bypassing the rear heater as I use the van to transport and the rear was not important to me and had several leaks, whoever the rest of the heater hoses had been removed from the front heater core but are now back in place and I thought I had the hoses routed right and the van was running at mid temp all summer but when I tried to use the defrost I was getting no heat, looked at vent doors and flow was ok but low velosity very little heat. I looked at heater hoses again and it seemed that the heater core was plumbed wrong so changed that to line from water pump to heater core and heatercore to intake as the hoses were looped so it could not circulate now the van runs cold and still very little heat even in the hoses but the engine never get to running temp just 2 bars, What happened and does anyone have a routing guide for the heater hoses as I have a repair manual that shows nothing in fact it was a wasted 25$ because it is useless. Rad cap was new as was new failsafe thermastat. Not much skin left on knuckles Help!