Mike
When you do the Vit engine in an sj you use the sj starter,unless its the skinny Bosch starter you have to trim the engine block a little bit, i am not sure whether the 410 and 413 starters are different.
As i said i have an unidentified starter in the garage (think its off a vit) you can borrow it to try if you want.
Been onto a few people in the area to see if anyone else has got one (no luck yet).
Ring me tonight might be able to drop it off on the way to Harborough tomorrow.
Regards
Steve