Hi, My Mk1 dash is in bad condition. Instead of chasing the parts that are hard to get and expensive I was thinking of changing it to a Mk2 dash. I have a good Mk2 dash and heater, apart from unpicking the old dash panel and welding in the Mk2 unit what other issues may I find?

You would need a Mark 2 Dash top from a panel van along with the steel work to match.

The Mk2 dash parts I have came out of a van. On a side note how hard would a factory aircon unit be to get?

Interesting that you should ask. 
 
I've always loved the look of the Mk1 Escort, but hated their dash. Much prefer a Mk2 RS2000 cluster. So when the opportunity came up to buy a Mk1 Escort with a Mk2 dash panel already installed, albeit incomplete as only the steel dash panel had been installed, I jumped at the chance. Little did I know what I was in for.
 
The following is what I have learnt:

1. You can't use the top cushioned crash pad from a Mk2 sedan or coupe, as they are too wide by about an inch. You need a Mk2 Panelvan crash pad. They are narrower, and will fit.
2. Since the crash pad is the narrower Panelvan crash pad, I can only assume that the steel dash panel installed in my Mk1 was originally from a Mk2 Panelvan, and that one out of a sedan or coupe would be too wide.
3. Don't bother retaining the Mk1 steering column. Shroud doesn't line up with remainder of Mk2 dash & centre console and it looks like absolute crap. Then there's the issue of the switches. Use a Mk2 column & indicator stalks etc... then your lights, horn, wipers & window washers switches will need to be moved.
4. Mk1 heater can't be used as you must retain window demisters and they now run in separate ducts, whereas in the Mk1 you simply rotate the vents upwards. And Mk2 had side vents.
5. In a Mk1 the wiper motor lives behind the cluster (in a RHD car), and in a Mk2 the wiper motor sits above the glove box. Want to know why? Because if you leave the wiper motor in its original position, behind the cluster, you can't fit the cluster into the dash and you can't fit the driver's side demister vent. Solution. Move the wiper motor to above the glove box like in a Mk2. Now your Mk1 wiper arms mechanism won't fit as it expects the motor to be behind the cluster. So fit the Mk2 wiper mechanism.

After all this, and many other sagas which I am doing my best not to remember, I came to the conclusion that in order to complete the conversion, and I had no option but to do so as the steel dash panel was already in place, I would need to buy a Mk2 Panelvan and simply transplant EVERYTHING from the van to the Mk1, including all the under dash wiring loom and graft it into the existing loom, so that is what I did.
 
Knowing what I know now, if I had a Mk1 with a standard Mk1 dash, I would simply upgrade to a 6 dial Twin Cam dash. Hell of a lot easier and you still get a good looking dash with useful information.
 
But then again, if you really like the Mk2 dash with an RS2000 cluster, and I do, then by all means, give it a go. But a word of advice, buy a Mk2 Panelvan first. Trust me. You're going to need it.
 
On a final note, as a result of the conversion I now own a 1973 Mk1 Escort that has hazard lights. You don't see that every day. :-)
 
 
 

Hi Chuff,  That is exactly the info I needed and expected. I was looking for a Mk1 for a long time and couldn't find one so I bought a Mk2 project and started working on it. Along the way I picked up a Mk2 bare shell. Then a Mk1 with rego turned up so I bought it and have been using some of the Mk2 parts to repair it. I was looking for a 6 dial dash but with the trouble I found getting parts like blinker switch and other switches and the price of them I looked closer at what I had. I can use the steel part from the spare body and all the other parts from the Mk2. There is loose parts in boxes the come with the Mk2 so I have plenty also have 2 RS2000 dashes and 1 Ghia. There in also several wiring looms. My windscreen frame has some rust that needs repair so I can  take the Mk1 dash out do the repairs and install the Mk2 unit. At least the parts for the Mk2 dash are easier to find and a lot cheaper. PS  I also have the Mk2 woodgrain panels.