360-383 A-debate...max builds need not apply.

Found it, sort of. I think I was thinking of the '72 Road Runner, which had the 400 4bbl as the standard motor and for an extra cost you could get the 340 4BBL.

https://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1972/72_Satellite_25.jpg

Not exactly what the OP is talking about though as it is a 400 vs. 340 comment instead of the 383 vs. 360.