The pages were not intended strictly for SEO value, they were mainly built for user value, i.e. returning a 100% focused page on the part number they searched for. Remember, many people use Google as a navigational tool and they also consider the product to the the part no. they searched for, not the main manufacturer of the product (ATE).
I understand what you are saying though and think building stronger product pages is the way to go, although I will try on a subset of pages and monitor results.
Now to decide which approach to take to yield the best results:
a.) SEO focus on ATE MK70 (list all the vehicle makes/models/years this product work on, including list of part numbers)
or...
b.) SEO focus on vehicle makes/model (then list all the manufacturers of suitable products, with corresponding part numbers)
Thanks,
Woody 
