For the front, measure the from the edge of the seat tube to the midpoint between the rings, then add 14.3mm (I think most ST are 28.6).
For the rear measure from the mid cog to the inside face of the dropout. Subtract that number from half of your frame dropout spacing dimension (126, 128, etc.)
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1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"