I would contact Clifford to see what they recommend for the lifters to go with that cam.
If you have the actual Corvette intake that uses the Carter side draft carbs, contact carbking on this forum to discuss rebuild kits. Do you already have the Vette carbs? If you don't, you're probably better off with a traditional triple that uses downdraft carbs instead of the Corvette triple. With more options, you'll have more success piecing together a matched set of downdraft carbs. With a good progressive linkage setup, you can set it up for reliable normal driving and have the other carbs kick in when you jump on it.
I don't think the 261 differs from the 235 as much as you're expecting it to, so trying to use all the 261 parts you can in your 235 won't do much for performance compared to the 235 parts you already have.
