Back again with an update for those who offered info&advice. My recently found '70F250CS was looking ill in the 360. Rough idle,low power,blue smoke,ect. Figured it would need a motor when I bought it. Then the family hauler went belly up and I spent the truck budget on a new minivan. Now for the good news! The 'ol FE will live. I found the weirdest thing causing most of the problems. She blew the first emissions test at 4 times the hydrocarbons limit with low CO. Things started making sense when I dropped the idle WAY down and checked rpm drop cyl to cyl. Right bank,two weak holes inboard-left bank,two weak holes outboard. BINGO-carb related! Sooo I pull the carb off again and take a REAL GOOD look again. What I found was sand packed up inside one of the emulsion tubes. Grains bigger than the primary jets! The only way I can figure they got there is by someone dropping the venturi assembly in the dirt while putting a kit in the carb. This carb looked clean and correct so I had ruled it out as a problem. I swapped in another venturi assembly from an old carb since the sand was permanently lodged in the other,slapped it back down and fired the old girl up again. Equal response from both idle screws,even rpm drop across all 8. Off to test, passed with flying colors,and my new old truck is legal,licensed and rolling up the road. She's still a little blue in the exhaust when I let off to shift, but not bad for a cheap, high miles, old truck. HAPPY ENDING. Once again, Thanks to everyone for your input and Thanks to the Big Boys who run this very nice site. V.M.