Referring to these handy charts, Sun electric showes what looks like two distributors, with two sets of advance for the 1956 Ford 272:
FDS12127A
Dist RPM           Vac.    Dist. Deg.
300                   .15"     0-1/2 deg
400                   .28"     1/4 - 1 1/4 deg
800                   .96"      6 1/2 - 7 1/2
1200                  2.21"    11 1/2 - 12 3/4 deg
1600                  3.41"     14 1/2 - 15 1/2 deg
2000                  4.60 "    16-17 1/4 deg
FDS12127B
300                   .16"       0-1/2 Deg
400                   .29"       0-1 Deg
800                    .88"      5 1/2 - 6 1/2 deg
1200                  1.27"      8 1/2-9 1/2 Deg
1600                  1.73"      11-12 deg
2000                  2.19"       13-14 1/4 deg
The Ford 1956 292 is identical to the second set above.
           
			    
				
			    Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor. 
