I have a gearbox minus bellhousing I'm not sure if it's for a viva/firenza/magnum or not- it's very similar to my magnum one but the rear transmission-to-propshaft "cover" (don't actually know what you call it- referred to as the rear cover assy in the catalogue I think) is different in that the gear selector mounting point is different.
These are the part numbers for HC transmission I have in my parts catalogue:
The transmission casing is the same- 7211158 but the rear transmission cover is different- 91011917. The whole gearbox assembly has a tag on it saying 91016258- it doesn't appear in my catalogue BUT 91016259 does as the full thing.
I either think it may be a late model or possibly something off a chevette or mk1 cavalier? Kind of perplexed as it is a same part number for a 1.8/2.3 transmission casing. It seems "about" the same length as a normal transmission. I think it's also possibly NOS.
Pics- this shows the difference
Any help much appreciated as this has been knocking about my garage for the past 30+ years