I have owned 69 & 70 R code Mustangs, as well as a 70 M code 351C 4V with Sheker. Both the 69 and 70 428 Shakers have 3 small angle mounts with studs to mount the Shaker top, the 351C Shaker base has an eccentric circular flanged ring that has the 3 studs welded to the ring. The only real differance that I have seen between a 69 Shaker, and a 70, is that the 69 has a curved steel elbow welded to the base at the front, for the fresh air hose from the valve cover filler cap, while a 70 uses a plastic 90 degree elbow inside a grommet for the same purpose.
428 powered Fairmont drag car, Best ET:9.97 @132.56MPH, best 60 ft: 1.29
59 Meteor 2 dr. sedan 332, Ford O Matic
74 F350 ramp truck 390 4speed
1985 Mustang 331 4 speed Best ET10.29at 128.7mph, 1.40 69 foot