Question for rear housing gurus

[RodnRudy]

So I advertised my 68 C10 rear end in the for sale section. Housing is stamped HA which is 3.73 gear ratio. A member said he would buy it but only wanted the ring&pinion, carrier etc. I agreed and yesterday pulled the carrier and pinion gear out and lo and behold the thing is a 2.76 gear ratio! It must have a series 2 carrier from a later than 72 12 bolt truck rear? I did some searching and found some one had an '85 truck rear with the 2.76 ratio. Question is will the later carriers inter change with the earlier 67/72 rear housings? Needless to say the sale went south but the buyer was glad I checked before I sent it to him. Pics of parts and housing stamp below. Tooth count on the pinion is 17 and on the ring gear is 47.