[ QUOTE ]
I thought the L88 'vettes used a 10.5" setup?
[/ QUOTE ]
The one I have out of a 69 L-88 is a 621 11". There may have been some applications for the 403 with a BBC in 65/66 but I remember 99% of 403's being installed with small blocks vetts and z-28 and the BBC getting the 621's.
