74/75 REPU information assistance

[Rotarydave]

I am working on fixing title issues on some of my trucks let me outline the problem. What is the definative cutoffs for 74 and 75 trucks. I have multiple pieces of documentation that only make things more confusing.

Here are the trucks in question with all the info I currently have and title info

1974 REPU build date 8/74 vin number PA136-109881
1974 REPU build date 8/74 vin number PA136-109985
1975 REPU build date 10/74 vin number SPA136-121457
1975 REPU build date 7/75 vin number SPA136-108888


Mazda data published in 1991 Vehicle ID Manual states that 1974 started at # PA136-100011, 1975 started at # SPA136-105776, 1976 started at # PA136-150001

Mazda data from REPU parts manual with monthly production breakouts states that production for 1974 started with PA136-100173 and 1975 started with SPA136-112286

the monthly breakout for numbers looks like this (begining number each month)
12/73 PA136-100173
1/74 100377
2/74 101495
3/74 102592
4/74 103660
5/74 104619
6/74 106113
7/74 107849
8/74 108699
9/74 110103
10/74 SPA136-112286
11/74 122309
12/74 -none
1/75 122359
2/75 122366
3/75 122369
no further production numbers for 1975

So here is my question how did I get a 1975 truck that shows it was built in 7/75 with a chassis number of 108888 and how come I have 2 74 trucks with chassis numbers that come after it 109881 and 109985 this shouldn't be possible becuase no trucks were built in 7/75 does anyone out there have a 75 truck that is similar, for example one built in 7/75 or a 74 truck that was built later in 74 like 9/74