Confused

[nsb29]

Well I’m finally home back in Florida I ended up using my old gears with new bearings and a new end yoke, now I’m in my on garage I can figure this out.the first gear was for a series 4 carrier and was 1/4 in thicker than my original, so they sent me another set and according to the numbers it’s for a series 3 Carrier for my year truck but it’s a 1/4 thinner than my original it’s like wtf is going on.
Apparently 373 was available in bought series 3 and 4. Also it seems Richmond gears are trying to cover too many years with one gear. Well update this once I figure this mess out but right now I believe it would take a1/4” shim to get the ring gear to meet the pinion this is stupid