P series trucks are kind of "homeless" here. Your P35 probably has more in common with an F350 of the same vintage. I see your post in the van forum--forget that, nothing in common with the E series.

P35 = P350 Parcel Delivery Chassis

B = 300 1V six cylinder gas engine

V = Kentucky Truck Plant

S14988 = 1974 numerical series

122 = 122 inch wheelbase

P351 = P350 parcel delivery chassis, 6,100 lbs GVWR

O = parcel delivery body type. The bodies are provided by another company.

J = Ford 3 speed automatic, probably the C6. (all aluminum one piece?)

25A
25 = Dana (Spicer) model 60, 5,200 lbs capacity, 4.56 ratio
A = Ford 3,800 lb capacity front axle. This shows as a special order item.

6100 = 6,100 lbs GVWR

52 = Dallas District Code.

No special order listed, but I think all the P series ended up with "special order" situations due to the body being provided to the 3rd party.

 

I own a 84 Ford Grumman stepvan w/351cid Windsor 2bbl carburetor. Its GVW is 11,000lbs

 

My stepvan was a FedEx truck out of Memphis Tenn

 

Looking for a wiring diagram for a 1977 ford gruman 4.9L inline 6 300

 

Is it a P series chassis? What are the first 3 characters of the VIN?