It can be done, I saw one on ebay a while ago...lol. Don't know what's involved though.
What I'd check:
See if you can check the differences between the steel tube crossmember thing that the dashes bolt to. see if they are much different between the two. if the are different see if the coily one bolts to the same place on the bodywork and by the same method.
I can't imagine the wiring should be too bad, maybe just extending a couple for the clock or something...?
The windscreen clamps; coilies don't have a fold down windscreen, will the dash prevent the windscreen clamps being used? (irrelevant for a hardtop obviously

)
If I was in your position, I'd buy the whole coily for $500 (assuming its not half gone or something), use the bits you want, then flog the rest off as parts.
Wheeling on completely wicked angles, without even looking stable.