I know there were only 1287 LT-1s made in 1970, but does anyone know the quantity made in coupe vs vertible and how about the number that were green/green. Trying to determine the rarity of the combo since the consensus seems to be to buy.
There are no records that provide actual engine/body style breakdown for the 1970 model year. I do know of one very extensive LT-1 survey that would seem to indicate approximately three coupes to one convertible (if trends are to be believed). This is simply an extrapolation of the available data so take it for what it's worth. The LT-1 convertible is certainly more desirable than the coupe from a value standpoint, but there is nothing at all inherently wrong with the coupe... Certainly nothing to keep you from buying one.
Donnybrooke green was a very popular color in 1970 and you tend to run across quite a few of them. I personally like it quite a bit (I was specifically looking for Donnybrooke green car when I purchased mine), but be advised that it is not a very popular color today... "No Sale" green as someone very aptly stated. I have seen a couple of Donnybrooke green/green vinyl interior LT-1s and while they may be "rare," I don't think I'd call the combination desirable. No matter though... At least you aren't likely to bump into a similar car anytime soon.
If the car is as nice as you stated (I take "excellent" body as no damage anywhere) it certainly sounds like a decent deal. MJ also pointed out that there are some pretty rare (and expensive) parts that always seem to be missing on these good deals... Carburetor... Alternator... Transistor ignition system... A.I.R. system. While these parts aren't absolutely required to drive the car and enjoy it, it will certainly impact the resale value of the car should you ever decide to sell it. Just something to think about.
As always, if you are not well versed on the details of these cars, then by all means take someone along that is (even if you do know a thing or two, an extra set of eyes never hurts). It could help you avoid problems down the road.
Good luck with your decision!