Mornin guys, seems from the hit counter we’ve got interest in these dash AC projects…..It’s Saturday and I’ve got some time so I would like to update where we are for those that are following this thread. The goal here is to document an effective way to not only renew the GMC dash but also integrate into the project a whole new dash AC/heat system update for all GMC models wether you have a type 1,2 or 3 systems. The coach that started all this , Ruby, is a 1973 coach which means it’s a type 1. Texas Tux that just came in to get the treatment and be another one of our Lab Rats is a 1976 which means it has the type 2 dash AC with the underdash 2 vent duct. The main box was still the same.
The dash AC/heat upgrade needs to be done in conjunction with a reworking of the complete dash and would probably be best done with one of Mac McNeal’s larger dash kits. Also a refinishing of the cosmetics of the dash all go to make the volume of labor cost effective. Everything benefits from doing this. So now while we’re waiting for our patterns I need to break Texas Tux to it’s root mean of dash AC and wiring to get it where Ruby is so we can start engineering the new system. With the operating room set, the stack of parts to the right of the pic will grow 
Ruby’s dash was @ like this when I went diver down into it. More stuff out and there’s more light on the firewall. 
It’s simply amazing to me how much cleaner the firewall can be without the dash AC box and all the associated wiring and hoses! 
We’ll go ahead and reuse the 130amp blue battery isolator… we usually use the original smaller 95amp hey but that’s fine, it’s just the right amount of overkill…. But taken to the bottom of the wiring this is the firewall at root mean 
and leaving yesterday evening along with having the old tiny slider toll booth windows out ready to get it’s new big sliders 
.and it’s interior pretty much apart 
all neatly stacked on palates 
I completed rewiring the DC primary wiring and switching for the batteries. If you follow the new 2ga. wiring… the left switch is living area battery the right engine and the upper sealed marine switch is to combine both systems. The 130 amp isolator is “biwired” with 2 8ga. wires to the terminals for increased current capacity and new battery boost and horn relays. The return duct vent was removed and plated over so Texas Tux is ready for it’s closeup. Ruby gets all this for 3 batteries on Monday…. 
On other things, Friday we delivered the Avion trailer … windows refinished and sealed, new roof AC, MaxVents and a 7″ screen motorized DIN radio. And it’s off for more fun 
This morning… my time… I took Attila out for some fresh non Ethanol fuel and breakfast at Dixie Belle …. nice nip (to me) in the air… was a great ride! For those who have not as yet met “Attila” , he is a 1966 Chang Jiang 750, a Chinese military side car bike…. 750cc, twin carb…18 horsepower. With 5.7 compression it will run on pretty much anything… not very well mind you, it doesn’t do that even with GOOD fuel
Hey but it’s old, I like old stuff so lets go out and have a fun weekend….. see ya on the other side…….
