The general rule FOR BEST RESULTS is to use the exact carburetors with the exact same calibration.

Now the question is, will what you have work? Probably, but so will hiring a 15 year-old to stand on the running board and pour fuel into the engine out of a leaky boot!

Will it work as well as you want it to? Depends on the skill of the 15 year-old wink or in the case of two different carbs it would depend on your access to a chassis dyno, a machine shop, and your skill as a tuner.

Would I do it? No.

And while there are no 966s or 2100s currently on ebay, there have been several of each sold in the last month. You can match either with a little patience.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop