The gap on the 351 Cleveland changes timing. Adjust the point gap until it is at 28-32 and begin timing then.
If the 360 is in a F100 the point gap is .021. If the 360 is in a F250 or bigger the point gap is .017.
( .044 inch ) according to motorcraft.com
( .044 inch ) for the 5.8 L / 351 cubic inch V8 engine in a 1997 Ford F-250 , according to motorcraft.com
( .044 inch ) 351 Windsor and 351 Modified for 1978 Ford truck
I BELIEVE the point gap is ( .017 ) and point dwell is ( 26 - 31 )
On your 1997 Ford F-250 Heavy Duty , 351 cubic inch V8 engine ( 5.8 liter ) Check the Vehicle Emissions Control Information ( VECI ) decal located in the front of your engine compartment ( it will show the type of spark plugs to use and the spark plug gap )
The spark plug gap for the 1979 Ford F250 is 0.044. This gap remains the same for the 1978 and the 1980 Ford as well.
0.044
.044 inch
The point dwell is 26 - 30 The point gap is .017 According to motorcraft.com ( one of Fords websites )
.044 inch for 351 M and 351 W