Many parts will physically bolt in place, but may not work correctly without modifying them some. This fact covers most years and models.
Keep in mind that quadrajets are application specific, and each unit was tuned exactly for the engine it ended up on. Swapping parts around, even though they fit, is "hit and miss" unless you set up the donor part exactly like the original part in all areas.
For example, a late 70's Chevy airhorn may physically replace an Olds airhorn, but will not work well due to having much larger main airbleeds.
It is always best to keep all the original parts together, and use parts from the same carburetor number when swapping them around. In all cases when parts for another carburetor are used, they should match up in every area exactly.
Our book covers recalibration, in addition to complete/correct rebuilding. This helps the tuner when setting up donor parts as the areas that need modified are clearly noted.....Cliff
