Check all of your connections to be sure they are clean and properly connected. Including ground. If all looks good you can cook your CDi box. I just recently did the cdi on a 88 300 and it worked.
put cdi box in oven at 450 for 7 minutes. With plug facing up.
aftermarket Carb I ordered is junk. No surprise from what I have read. Just noticed there is also no spark. Tested out all the components, and in attempting to test the CDI, I get no reading across any of the terminals whatsoever. It ran when I bought it, so I find it really odd that the CDI would be bad all of the sudden.
In looking online, the aftermarket ones seem to have a BAD history of not working at all, and the OEM CDI is $200.
If I were certain this is the issue, that would be one thing, but it worked for 40 years and then it just broke when I brought it home???
Really regretting buying this pos at this time. Might as well have thrown money down a garbage disposal.......