320/351m

will a elect dist from a 302 fit a 77 351m
302 year unknown

my guess would be 'No', as the 302 is a smaller block that the 351M

A 302 Distributor should fit 221, 255, 260, 289 and 302 V8s. The 351 Windsor has a one inch taller deck height and the distributor will not fit even though it is from the same engine family. The 351 M is from a different engine family and the 302 distributor will not fit.

351C, 351M, 400, 460 all same distributor.

will a elect dist from a 302 fit a 77 351m
302 year unknown
if the distributor is the same lenght as the 302 (which I doubt) you could use the gear off the 351m dist. and it should work.